Sample #1

dissertations thesis

One-of-a-kind and never resold!

thesis help

Our one-of-a-kind writing is guaranteed to match your specifications!

Sample #1Sample #2Sample #3


Sample #3

This is a master-level, nutritional biology thesis of 51 pages (13,895 words).

Chocolate: Behind Its Bad Rap

Chapter One -- Introduction to the Problem

Introduction to the Problem

In today's society, chocolate is everywhere.  It seems that people have developed a love-hate relationship with chocolate.  According to the US Department of Commerce, the average American ate 11.7 pounds of chocolate in the year 2000.  American adults ranked chocolate as the most-craved food and favorite flavor by a three-to-one margin.  (Mustad, 2001)

Throughout the world exists a society of chocolate lovers.  While Americans consume an average of nearly 12 pounds of chocolate per year, we are not the biggest fans.  The British eat 16 pounds each and the Swiss, inventors of milk chocolate, consume the most yearly at 22 pounds per person.

However, while people love it, they can't help feeling a pang of guilt when eating it because over the years, chocolate has gotten a "bad rap" as being an unhealthy food.  However, recent research is slowly unraveling the hidden truth about chocolate – that it might actually be beneficial to a balanced diet.  (Bloom, Mustad)

Despite its name, a typical "milk" chocolate bar provides less than 10 percent of the daily recommended amount of calcium.  But, surprisingly, a government survey shows that chocolate and products containing chocolate make substantial contributions to our daily intake of copper, an essential mineral in the prevention of anemia and, possibly, heart disease and cancer.  Chocolate also provides significant amounts of magnesium, which plays a role in regulating blood pressure and building bones.  (Edmundson, 1996)


Chocolate Myths

Before examining the possible benefits of chocolate, it is important to understand the myths surrounding the delectable food. 

Many people believe that the fat in chocolate will cause high levels of cholesterol in the blood.  However, since it is a product of plants, chocolate does not contain cholesterol.  It is actually saturated fat that is the culprit of increasing cholesterol in the blood.  (Bloom)

Stearic acid, which is the main saturated fat found in chocolate, does not raise blood cholesterol levels.  A study in which subjects consumed a 1.4 oz.  chocolate bar instead of a high carbohydrate snack revealed that the chocolate bar did not raise low-density lipoprotein levels, known as LDL or "bad cholesterol," but actually increased high-density lipoprotein levels, known as HDL or "good cholesterol."

Many people also look down at chocolate as completely lacking in vitamins and minerals but this is also untrue.  When comparing the nutritional values of chocolate milk with regular milk, it is easy to see that chocolate milk has much more sugar than regular milk.  Still, it also contains higher levels of zinc, potassium, copper and magnesium.  (Steinberg, 2001)

Solid chocolate is a major source of copper, which helps the body use iron and aids in the development of connective tissue, blood vessels, and skin, and magnesium, which is part of the bone structure and plays an important role in the nervous system and in the break down of protein.  Another bonus for chocolate milk is that children are more likely to get more of these valued nutrients when offered chocolate milk because they tend to drink two-thirds more chocolate milk versus plain milk.

Contrary to popular belief, chocolate does not cause acne.  In a 1970's study carried out at the University of Missouri, test subjects who believed their acne problems got worse within 36 hours of ingesting the "culprit" food were given the equivalent of 230g of chocolate and then observed every day for the week following.  (Steinberg, Bloom)

To the amazement of all, no increases in acne were found in response to the food challenges.  In a recent study by the University of Pennsylvania and the U.S.  Naval Academy, 65 acne sufferers began to consume large amounts of chocolate.  46 showed no change in their condition, 10 got better and nine got worse.  This indicates that acne is not related to chocolate consumption.  Further studies show that it is related to hormonal changes that create activity of the skin's oil glands.

Additionally, chocolate is not high in caffeine, as many people think.  The amount of caffeine in a typical 1.4 oz.  bar or an 8 oz.  glass of chocolate milk is equivalent to a cup of decaffeinated coffee with 6 mg caffeine.  An ounce of bittersweet chocolate has more; from 5-35 mg caffeine and 1 ounce unsweetened baking chocolate has 35 mg.  These levels are all well below the 140 mg that is in a cup of brewed coffee.  Stimulant effects of caffeine can be initiated after consuming 150-200 mg, but this varies from person to person.  (Edmundson)

Almost everybody remembers their parents telling them that chocolate causes cavities.  But candy alone does not.  Susceptible teeth, dental plaque, and food cause cavities.  In fact, chocolate and cocoa have the ability to offset the acid-producing potential of the sugar they contain. 

Milk chocolate has a high content of protein, calcium, phosphate and other minerals, which have protective effects on tooth enamel.  Also, since it contains fat, milk chocolate clears the mouth relatively faster than other candies, so milk chocolate may be less cavity causing. 

There is little evidence that chocolate is addictive, although those craving it would say otherwise.  The substances found in chocolate do not appear in high enough amounts to exert any significant influence.  The most likely explanation for cravings is psychological or sensory.  Researchers have found that chocolate aroma has a powerful calming effect.  According to Dr.  Neil Martin, a senior lecturer in neuropsychology, the sweet smell "may remind people of certain things that are relaxing - or something could be tapping into the sub-cortical emotional centre." (Vinson, 2001)

Researchers at Dundee University suspect the "craving" is simply due to the deep-rooted pleasure of eating chocolate, a combination of sweet taste and creamy texture.  Another possibility is the "naughty but nice" factor many people associate with this delicious snack food.  (Vinson, Bloom)

The final basic myth surrounding chocolate is that it makes children hyper.  However, both the FDA and 1988 Surgeon General's Report on Sugar and Health support findings that neither chocolate nor sugar causes hyperactivity.  It is more likely that the environments in which these foods are served are what cause children to get excited.


Statement of the Problem

Research that portrays chocolate as a healthy food may encourage chocoholics to toss aside their feelings of guilt and indulge to their heart's content.  After all, research shows that chocolate is good for the heart.  However, many agencies, such as the British Heart Foundation, are arguing that advising people to eat chocolate regularly is a reckless message that should be ignored.  A more accurate message would be, according to the British Heart Foundation, to "enjoy a little chocolate in moderation, but ensure you eat five portions of fruit and vegetables daily to get all the flavonoids you need without the added fat." (Steinberg)

For example, research has shown that high amounts of flavonoids, which are found in chocolate, may also positively affect mechanisms involved in the maintenance of cardiovascular health.  However, this information does not mean that large amounts of chocolate in the diet are going to prevent heart disease. 

The purpose of this study is to show that chocolate can be taken off the "guilty foods" list and added to the list of foods that are a part of a healthy diet.  But it is important to also show the damaging effects of eating chocolate, which may be downplayed by the newest research promoting chocolate. 



For years chocolate has gotten a bad rap for being a guilty indulgence." Seen as a food with a distinctive and tempting flavor that was resisted by health-conscious individuals, this reputation can be seen in the fact that chocolate cake is often called "devil's food." (Coe, 1996)

There are many reasons that chocolate was seen as an unhealthy food.  Many health officials labeled chocolate as being associated with fat and refined sugar.  It was also said to have high levels of caffeine, and be a contributing factor in a variety of problems, including heart disease and obesity.

This study will show that a lot of chocolate's bad reputation is undeserved.  For example, the link between chocolate and disorders, such as obesity and heart disease, is not due to chocolate itself but rather all the high-fat, high-cholesterol butter and cream that is used in chocolate candies and baked goods. 

Interestingly, cocoa has actually been used for centuries as an herbal medicine.  Central Americans have used cocoa to treat a great variety of things, including fevers, coughs and discomfort associated with pregnancy.  There is also evidence that hints that cocoa can be a digestive aid that boosts blood flow to the heart and is useful in helping victims of chest congestion breathe easier.  (Young, 1994)

Tests performed by a professor of nutrition and internal medicine on more than 100 volunteers who ate either small amounts of chocolate or who consumed flavonoid-rich cocoa beverages, indicated that the flavonoids in chocolate—compounds that naturally occur in many fruits and vegetables, but are particularly plentiful in cocoa beans—confer helpful effects similar to those produced by low doses of aspirin. 

Public health officials often suggest that individuals over the age of 40 take a baby aspirin a day to reduce their risk for stroke and heart attacks.  In the United States, it is estimated that millions of individuals take aspirin on a daily basis for its cardio-protective effects.

Scientists have also found that the flavonoids in chocolate may augment the natural oxidant defense systems in the body, which may reduce the risk for certain diseases. 

Still, nutrition experts caution that chocolate, which is rich in sugar and fats, should not be viewed as a substitute for fruit and vegetables.  Similarly, flavonoid-rich foods should not be viewed as a substitute for low-dose aspirin.  This study will examine both the benefits and risks of chocolate in the diet.


Research Questions

How has chocolate gotten a bad rap for being an unhealthy food?

What proof do we have that is a healthy food?

Are the studies on chocolate biased or incomplete?

What are the positive and negative ingredients of chocolate?

How can chocolate be beneficial to a balanced diet?

In what ways can chocolate be harmful to the body?

How has chocolate been used and abused throughout history?

What do nutritionists say about chocolate?

How is chocolate good for the heart?

How is chocolate good for the brain?

What role do the manufacturers of chocolate and chocolate products play in today's research?

Is chocolate a health food?

What kind of research needs to be done in the future?

Are men and women equally attracted to chocolate?



The purpose of this study to show that chocolate does not deserve the bad rap that it has gotten as an unhealthy food.  With a well-balanced diet, eating moderate amounts of chocolate can be beneficial.  Still, this study is aimed at providing a complete picture of the studies that have been conducted on chocolate.  It is important to know both sides of the story. 

While many myths regarding chocolate have been proven wrong, there are still negative effects of eating chocolate.  Chocolate is rich in calories and saturated fat, which can lead to disease and obesity.  Also, chocolate can be bad for some people. 

Chocolate, as well as red wines and certain cheeses, contains phenylethylamine (PEA), a substance that can dilate blood vessels in the brain.  People with sensitivity to PEA might find that eating chocolate triggers headaches, even migraines.  (Mustad, 2001)

This study will also examine which types of chocolate are most beneficial and which are lacking in nutritional value.  It is my goal to prove that chocolate can be beneficial to the diets of many people, provided that they eat it in moderation and in combination with a healthy, well-balanced diet.


Significance of the Study

While initial research on the benefits of chocolate is encouraging, it is obvious that large-scale, controlled human studies are missing and more research is needed. 

Chocolate was long believed to be a source of saturated fats, a type of fat that can have negative effects on overall health.  More recently however, a number of studies have identified the fat in chocolate as being stearic acid, a type of fat that the body converts through a series of biochemical changes, into oleic acid, which does not have the same deleterious effects. 

The problem lies with the type of chocolate.  Rich, dark chocolate with at least 70% cocoa content is a potential source of antioxidants, but what makes up the remaining 30%?

Also, it appears that many studies that have been performed have been minimal and their results have been somewhat misleading.  It is important to examine the facts and the result of the research to come to a conclusion about whether chocolate is good, bad or both.


Definition of Terms

**All definitions taken from the American Heritage Dictionary of the English Language, Fourth Edition. 

Acne- an inflammatory disease of the sebaceous glands and hair follicles of the skin that is marked by the eruption of pimples or pustules, especially on the face.

Anandamide- a messenger molecule that plays a role in pain, depression, appetite, memory , and fertility.

Antioxidants- a substance, such as vitamin E, vitamin C, or beta carotene, thought to protect body cells from the damaging effects of oxidation. 

Calories- a unit of energy-producing potential equal to this amount of heat that is contained in food and released upon oxidation by the body.

Catechins- a crystalline substance, C15H14O6, derived from catechu and used in tanning and dyeing.

Chocoholic- a person who craves chocolate.

Cholesterol- a white crystalline substance, C27H45OH, found in animal tissues and various foods, that is normally synthesized by the liver and is important as a constituent of cell membranes and a precursor to steroid hormones.  Its level in the bloodstream can influence the pathogenesis of certain conditions, such as the development of atherosclerotic plaque and coronary artery disease.

Conching- a flavor developing process that kneads the chocolate.

Depression- a psychiatric disorder characterized by an inability to concentrate, insomnia, loss of appetite, anhedonia, feelings of extreme sadness, guilt, helplessness and hopelessness, and thoughts of death.

Fats- macronutrients which are essential to life and provide a useful source of energy while insulating the body and its organs against the cold.  They also build and maintain body tissue while assisting in the transport of fat-soluble vitamins throughout the body.

Flavanoids- a a grouping of micro-nutrients are 12 classes that individually total over 20,000.  One plant or herb may contain hundreds of flavonoids.  The more well researched flavonoid classes are flavones, flavonols, isoflavones, quercetin, anthocyanidins, and catechins.  Flavonoids therefore make up the largest group of anti-oxidants.

Hyperactive- highly or excessively active.

Magnesium- a light, silvery-white, moderately hard metallic element that in ribbon or powder form burns with a brilliant white flame.  It is used in structural alloys, pyrotechnics, flash photography, and incendiary bombs.

Nutrient- any substance that provides essential nourishment for the maintenance of life.

Obesity- the condition of being obese; increased body weight caused by excessive accumulation of fat.

Oleic Acid- an oily liquid, C17H33COOH, occurring in animal and vegetable oils and used in making soap.

Palmitic Acid- a fatty acid, C15H31COOH, occurring in many natural oils and fats and used in making soaps.

Phenylethlamine- a chemical that speeds up the flow of information between nerve cells.

Phosphate- a molecule containing a phosphorus atom.  Phosphate is used by life to carry energy from one molecule to another in ATP.  It is also part of RNA and DNA.

Phytochemicals- non-nutrient plant chemicals that contain protective,
disease-preventing compounds.

Plyphenol- a substance made when plants go through photosynthesis.  It's contained in most plants.  In red grapes, tannin and risberitol are the two main types, and in green tea, it's katekin, which is well known.

Potassium- a soft, silver-white, highly or explosively reactive metallic element that occurs in nature only in compounds.  It is obtained by electrolysis of its common hydroxide and found in, or converted to, a wide variety of salts used especially in fertilizers and soaps.

Protein-Protein is a macronutrient, composed of amino acids, that promotes the growth and repair of body tissue such as skin, muscle and hair.  The daily-recommended intake of protein, depending upon age and gender, can range between 40 grams and 105 grams.  Protein is most often found in meat and animal products such as milk and eggs, but can also be found in plant foods like nuts and beans.

Saturated Fat- a fat, most often of animal origin, that is solid at room temperature and whose fatty acid chains cannot incorporate additional hydrogen atoms.  An excess of these fats in the diet is thought to raise the cholesterol level in the bloodstream.

Stearic Acid- a colorless, odorless, waxlike fatty acid, CH3(CH2)16COOH, occurring in natural animal and vegetable fats and used in making soaps, candles, lubricants, and other products.

Sugars- carbohydrates, which are macronutrients that serve as the main source of energy for the body.  Most carbohydrates consist of a combination of one or more of three single-molecule sugars: glucose, fructose and galactose.  Starch consists of long chains of glucose molecules linked together.  Table sugar, or sucrose, consists of two sugar molecules (one glucose and one fructose) linked together. 

Theobromine- a bitter, colorless alkaloid, C7H8N4O2, derived from the cacao bean, found in chocolate products and used in medicine as a diuretic, vasodilator, and myocardial stimulant.

Zinc- a bluish-white, lustrous metallic element that is brittle at room temperature but malleable with heating.  It is used to form a wide variety of alloys including brass, bronze, various solders, and nickel silver, in galvanizing iron and other metals, for electric fuses, anodes, and meter cases, and in roofing, gutters, and various household objects.


Chocolate: Behind Its Bad Rap

Chapter Two – Review of Related Literature and Research


Review of Related Literature and Research

Despite the fact that chocolate has gotten a bad rap over the years, many studies show that, in many ways, it is a healthy food.  Particularly over the past decade, scientists, professors, nutritionists and researchers have completed projects that show that chocolate can be good for people.

Studies on chocolate are varied and each one gives a different reason for the popularity of the food.  One conclusion is that this food holds benefits for humans in several different ways.  Health wise chocolate has components that help fight heart disease.  It also has the ability to make people happier and gives a boost of energy. 

All of the studies prove that chocolate is unlike any other sweet.  The reasons for these differences are not yet completely understood.  However each study is helpful in understanding the science of chocolate.  Today, the benefits of eating chocolate outweigh any negative effects of the food, but there are still so many gray areas surrounding the research.

A team of scientists has disproved the theory that if something tastes good, it must be bad.  The book, Chocolate and Cocoa: A Review of Health and Nutrition, which was commissioned by the International Cocoa Organization (ICCO) and produced in cooperation with the International Cocoa Research Foundation (ICREF), the educational foundation of the American Cocoa Research Institute (ACRI), discusses the latest research on the potential benefits of chocolate and cocoa. 

The book has revealed that:

  • Chocolate lovers can take heart in new research showing that this favorite food is packed with high-quality polyphenol antioxidants that may reduce the risk of developing cancer and heart disease. 
  • Stearic acid, the main saturated fatty acid in chocolate, does NOT raise blood cholesterol levels. 
  • It is chocolate's unique taste and sensory properties that make chocolate the single most craved food in the United States. 
  • Cocoa and chocolate are rich in minerals the body needs, including magnesium and iron. 
  • The vast majority of evidence suggests we dismiss the hypothesis that chocolate is a significant migraine trigger. 
  • Chocolate has relatively little impact when it comes to causing dental caries.  Chocolate tends to clear the mouth quickly, limiting the time it is in contact with the teeth. 
  • Allergies to chocolate are extremely rare with the more likely allergens being milk, egg, peanut or tree nut components of chocolate products - not the chocolate itself. 

Chocolate and cocoa do not cause obesity.  It is the quantity of foods eaten, combined with the level of physical activity and underlying genetics, which determine whether a person will gain weight.

According to several recent studies, chocolate is rich in flavonoids, which are the natural chemicals that make red wine healthy.  There are actually more flavonoids in two spoons of cocoa than there are in a glass of red wine.

In addition, chocolate contains stearic acid, which is useful in preventing blood clots.  Researchers have also found that chocolate is a potent "happy" cocktail of ingredients.  It contains caffeine, which is a known stimulant and mood enhancer; and theobromine, which acts as a muscle stimulant. 

Chocolate also contains a small dose of anandamide, which is a chemical that stimulates the same part of the brain that marijuana does.  However, a person would have to consume 25 lbs.  of chocolate during one sitting to get the same effect as marijuana would provide.  This explains why eating chocolate makes people feel good, and why some people crave chocolate all the time.

Chocolate also contains potent doses of the polyphenol antioxidants commonly found in green tea.  These polyphenols have been proven to protect chocolate from oxidation, which explains while chocolate does not spoil.  They are also proven forms of protection from cancer.

Many myths have contributed chocolate's bad reputation.  For instance, many people believe that chocolate adds a lot of calories and fat to our diets.  However, research performed by Mars, Inc.  and several universities shows that less than two percent of fat in the average diet is actually contributed to fat in most developed countries.  (Edmondson, 1996)

In these countries, most of the fat comes from meat and dairy products.  As long as the diet includes calories from a variety of food, chocolate can be safely included in a nutritious balanced diet, according to research.


Chocolate For the Heart

Phytochemicals called flavonoids that are found in cocoa have two positive effects.  First of all, the antioxidants block arterial damage caused by free radicals.  These unstable molecules (free radicals) may damage the arterial walls by blocking the artery wall lining.  The second indicates, that chocolate inhibit platelet aggregation which could cause a heart attack or stroke.  (Vinson, 2001)

There have also been studies indicating that cocoa flavonoids relax the blood vessels that inhibit an enzyme that causes inflammation.

Flavonoids and the subgroup called catechins are found in dark chocolate at four times the amount that is found in green tea.  Antioxidants block the free radicals that are breakdown normal cell reproduction.

Phenylethlamines found in chocolate act as a mood altering mild aphrodisiac.  This helps people who suffer from depression.

A recent study by Holland's National Institute of Public Health reveals that chocolate contains up to four times the anti-oxidants found in tea.  Researchers found that chocolate, particularly dark chocolate, contains 53.5 mg of catechins per 100 grams.  Catechins are the powerful anti-oxidants that help prevent against cancer and heart disease.  By contrast, 100 ml of black tea contains a mere 13.9 mg of catechins.  (Steinberg, 2001)


UBA and UC Davis Studies

Teams of researcher from the University of California, Davis (UC Davis) and the University of Buenos Aires (UBA) have discovered that chocolate contains compounds that may promote heart health. 

In one study, directed by Carl Keen, professor and chair of the department of nutrition at UC Davis, subjects drank a flavonoid-rich chocolate cocoa beverage.  Flavonoids are the largest group of plant polyphenols, an extensive class of antioxidant phytochemicals found throughout the plant kingdom.  The consumption of plant-derived flavonoids has been associated for some time with a decreased risk of cardiovascular disease.  (Edmondson, Steinberg, Rozin)

Analysis of the participants' blood revealed that over a six-hour period after drinking the beverage there was a decrease in platelet activation and aggregation, factors that may play a role in the progression of heart disease.

In another study, researchers in the laboratory of Cesar Fraga, professor of physical chemistry at UBA's school of pharmacy and biochemistry, fed participants M&M's Semi-Sweet Chocolate Mini Baking Bits.  Fraga and colleagues found that within two hours after ingestion the chocolate led to better absorption of some procyanidins, in addition to an increase in blood antioxidant capacity.

Procyanidins are polyphenolic compounds found in several plant species and commonly consumed foods, including cocoa, tea, grapes, almonds, apples, wine and strawberries.  It is believed procyanidins act as antioxidants, modulating key biological pathways in mammals.  They may also help protect cells in the body from the potentially harmful effects of free radicals, which have been linked to certain age-related chronic diseases.

That's not all.  The researchers also saw a decrease in blood lipid damage by free radicals, a positive development associated with the prevention of heart disease. 

"The findings of these studies are consistent with what we might expect to see based on work with other flavonoid-rich foods, such as green tea and red wine, as well as other fruits and vegetables," says Keen.  And, he adds, the results of these pilot human trials on chocolate's potential health benefits correspond nicely with earlier in vitro research.

Previous test tube studies have suggested polyphenols found in chocolate may decrease LDL cholesterol oxidation and modulate platelet activity, two potential contributors to cardiovascular disease.  In addition, earlier epidemiological studies have associated the consumption of chocolate with improved cardiovascular health.  Even so, Keen was somewhat surprised to see the platelet effect to the extent they did.


Saturated Fat

In Keen's study, the fat content of the cocoa beverage was 10%, with a saturated fat level of around 5%-7%.  But there is a big difference between the cocoa beverages and some commercial chocolates.  (Steinberg, Rozin)

The fat in chocolate from cocoa butter is comprised of oleic acid, a monosaturated fatty acid, as well as stearic and palmitic acids, chemically classified as saturated fatty acids.  In previous studies, oleic acid was shown to possibly have beneficial cardiovascular effects. 

Several studies have also provided evidence that unlike other saturated fats, stearic acid has a neutral effect on blood cholesterol.  Other test tube and clinical feeding studies have shown that stearic acid can decrease platelet activity.

So it appears that the potential benefits of chocolate outweigh the negatives.  Mars, makers of M&MS, and Snickers and Milky Ways, provided the funding for this project, which leads skeptics to believe that it may be biased.


Research on Tooth Decay and Chocolate

Chocolate could help prevent tooth decay, according to scientists at Japan's Osaka University.  The husks of the cocoa beans from which chocolate is made contain an antibacterial agent that fights plaque.  These husks are usually discarded in chocolate production, but in future they could be added back in to chocolate to make it dental-friendly.  (Mustad, 2001)

They concluded that the cavity-fighting action of cocoa bean husks isn't enough to offset decay caused by chocolate's high sugar content, however, so chocolate isn't going to replace toothpaste any time soon.


AAAS Preliminary Findings

At a symposium held during the 2000 Annual Meeting and Science Innovation Exposition of the American Association for the Advancement of Science (AAAS) in February, researchers presented preliminary findings from human trials that suggest that the consumption of certain chocolate products have a positive impact on blood markers associated with heart health.  (Mustad)

In one study, subjects who had consumed "M&M's"Semi-Sweet Chocolate Mini Baking Bits displayed a dose-response effect (the more eaten, the more flavonoids seen in the blood) in flavonoid levels in the blood within two hours, and an increase in blood antioxidant capacity. 

Antioxidants are important because they are believed to help protect tissues and cells in the body from the potentially harmful effects of free radicals, which are suspected of contributing to certain age-related chronic diseases.  The researchers also observed a decrease in the oxidation of blood lipids, which is considered positive for heart health.

Another study suggested that platelet activation and aggregation (factors that are believed to be markers in the progression of heart disease) decreased over a six-hour period after consumption of a cocoa beverage.  (Steinberg)

The promising results of these pilot human trials correspond with earlier test tube research and justify further research to confirm the suggestion that, with balance and moderation, chocolate consumption as part of a healthy diet may support heart health.

Platelets are the smallest of the red blood cells that when activated can clump together and form clots to stop bleeding.  It is thought that overactive platelets play a role in the progression of heart disease


Can Chocolate Provide a Long Life?

Researchers at Harvard University have carried out experiments that suggest that if you eat chocolate three times a month you will live almost a year longer than those who forego such sweet temptation.  (Mustad)

However, Harvard research also suggested that people who eat too much chocolate have a lower life expectancy.  Chocolate's high fat content means that excess indulgence can contribute to obesity, leading to an increased risk of heart disease.

The study suggests eating chocolate in moderation and to opt for dark chocolate.  It's higher in cocoa than milk chocolate and helps to increase levels of HDL, a type of cholesterol that helps prevent fat clogging up arteries.


Chocolate and Endorphins

According to recent studies at New York University, chocolate stimulates the release of endorphins, natural body hormones that generate feelings of pleasure and well-being.  (Piotrowski)

There are also many chemical elements specific to chocolate that may help to stimulate cravings.  In fact, chocolate contains over 300 chemicals and it is not known how all of these affect humans.

Many women report particular chocolate cravings when pre-menstrual.  This is possibly because chocolate contains magnesium, a shortage of which can exacerbate pre-menstrual tension.  Similar cravings during pregnancy could indicate mild anemia, which chocolate's iron content may help to cure.

Central nervous stimulants such as caffeine are also present in small amounts, and this has a mild effect on alertness as we know from drinking coffee.  Another mild stimulant present in chocolate is theobromine, which also serves to relax the smooth muscles in the linings of the lung.  Chocolate also makes people feel good by reacting with their brains.


Allergies May Be A Hoax

Further studies show that true chocolate or cocoa allergy is rare even though many people claim to be allergic to it.  According to research funded by Hershey products, only one out of every 500 people who thought they were allergic to chocolate actually tested positive.  Because people complain of headaches and migraines after eating chocolate, they assume it is an allergic reaction.  These reactions may be due to a food intolerance or sensitivity not an actual food allergy.  (Mustad)

It is also possible that ingredients added to chocolate during processing, such as corn syrup, milk, soybeans, lecithin, gluten, and nuts could cause adverse reactions.


On the Negative Side

With all the hype about chocolate and how good it can be, it is important to include research that looks at the negative side of eating chocolate.

Scientists have discovered over the last few decades that chocolate may cause headaches, obesity, heartburn, rectal itching, coronary problems, and emotional problems such as feelings of anger, irritability, confusion, and depression.  (Coe, 1996)

Caffeine, a stimulant, can cause anxiety, sleep problems, heartburn, restlessness, and difficulty with concentration.  Headaches and fatigue are usual signs of withdrawal from caffeine.  Although there is much less caffeine in chocolate than in a cup of coffee, small amounts can add up.  (Dillinger, 2000)

Theobromine occurs naturally in cacao beans and stimulates the nervous system and heart rate.  It may affect emotional moods as a natural antidepressant.  It is also a mild diuretic. 

Phenyethylamine affects mood swings by causing an initial emotional high then a short time later an emotional low.  It causes blood pressure and blood-sugar levels to rise, resulting in a feeling of alertness and contentment. 


Unhealthy In the Minds of Most

A 2002 Healthy Living survey sponsored by Speak Out showed that people still consider chocolate an unhealthy food, and their favorite one at that.  The chart below shows the top favorite "unhealthy" foods of the respondents.  (Speak Out)


Favorite "Unhealthy" Foods













Ice Cream



Fried foods






Fast food






Cake/baked goods






Breakfast foods










A research report titled "Chocolate: Food or Drug?" says that although addictive behavior is generally associated with drug and alcohol abuse or compulsive sexual activity, chocolate may evoke similar psychopharmacologic and behavioral reactions in susceptible persons.  (Bruinsma, 1999) A review of the literature on chocolate cravings indicates that the appeal of chocolate, such as fat, sugar, texture, and aroma, is likely to be a predominant factor in such cravings.

Other characteristics of chocolate, however, may be equally as important contributors to the phenomena of chocolate cravings.  Chocolate may be used by some as a form of self-medication for dietary deficiencies or to balance low levels of neurotransmitters involved in the regulation of mood, food intake, and compulsive behaviors. 

According to the study, chocolate cravings are often episodic and fluctuate with hormonal changes just before and during the menses, which suggests a hormonal link and confirms the assumed gender-specific nature of chocolate cravings. 

Still, the study shows that chocolate contains several biologically active constituents, all of which potentially cause abnormal behaviors and psychological sensations that parallel those of other addictive substances. 

Most likely, a combination of chocolate's sensory characteristics, nutrient composition, and psychoactive ingredients, compounded with monthly hormonal fluctuations and mood swings among women, will ultimately form the model of chocolate cravings.  It emphasizes that dietetics professionals must be aware that chocolate cravings are real.  (Kurzer, 1999)

The psychopharmacologic and chemosensory effects of chocolate must be considered when formulating recommendations for overall healthful eating and for treatment of nutritionally related health issues. 

During a double-blind study of headache at the University of Pittsburgh, scientists used chocolate as the active agent and carob as the placebo.  (Scharff, 1997) The chocolate and carob samples were formulated to duplicate products used in an earlier study in which strong differential effects between the ability of chocolate and carob to trigger headache in migraine were shown.  Sixty-three women with chronic headache (50% migraine, 37.5% tension-type, 12.5% combined migraine and tension-type) participated in the study.  (Steinberg, Kurzer)

After 2 weeks of following a diet that restricted vasoactive amine-rich foods, each subject underwent double-blinded provocative trials with two samples of chocolate and two of carob presented in random order.  Diaries were maintained by the subjects throughout the study, monitoring diet and headache. 

The results demonstrated that chocolate was not more likely to provoke headache than was carob in any of the headache diagnostic groups.  These results were independent of subjects' beliefs regarding the role of chocolate in the instigation of headache.  Headache diagnosis and the concomitant use of additional vasoactive amine-containing foods were also not associated with chocolate acting as a headache trigger. 

Thus, contrary to the commonly held belief of patients and physicians, chocolate does not appear to play a significant role in triggering headaches in typical migraine, tension-type, or combined headache sufferers. 

According to a Northwestern University study, individuals' ratings of the pleasantness of eating chocolate were associated with increased blood flow in areas of the brain, particularly in the orbital frontal cortex and midbrain, that are also activated by addictive drugs such as cocaine.  (Small, 2001)

The researchers of the study gave 15 study participants, who classified themselves as "chocoholics," between 16 to 74 squares of chocolate (or about 40 to 170 grams) that had to melt slowly in the mouth.  The researchers measured brain activity of participants, as they became full and then beyond full to the point where they ate despite no longer wanting to. 

The researchers learned that the brain regions activated by eating chocolate when it is rewarding are quite different from those areas that are activated by eating chocolate when it is perceived as aversive, as a result of having eaten too much chocolate. 

Many food scientists have reported chocolate to be the single most craved food.  Some researchers have even argued that chocolate is addictive.

In a 2000 report by the Laboratory of Toxicology, a case was presented involving chocolate cannabinoid mimics, which have been utilized in court by the defendant's lawyer in order to clear the accused of smoking and dealing in marijuana after he was found positive for cannabis in a routine urine immunoassay screening test.  (Tytgat, 2000)

The argumentation in this case was that the accused had supposedly eaten a massive amount of chocolate, which contained anandamide-related lipids.  These lipids inhibit anandamide hydrolysis in the brain, act as cannabinoid mimics and, according to the lawyer, were the cause of the positive cannabinoid test. 

To investigate this in detail, we synthesized N-oleoyl- and N-linoleoylethanolamide and spiked these compounds together with N-arachidonoylethanolamide in urine for immunological investigations.  None of the samples were found positive, indicating that no cross-reactivity occurs with cannabinoids.  As a result, the lawyer's claim could be refuted and the accused was convicted. 

A study by the University of Canterbury was conducted in 1999 to test if suppression frequently results in subsequent hyperaccessibility of the suppressed thoughts.  (Bulik, 1999) This study investigated whether this effect transfers to behavior.  Does suppressing thoughts result in a subsequent increase in the performance of behaviors related to those thoughts?

Twenty chocolate cravers and 22 noncravers were instructed to suppress chocolate-related thoughts in an articulated thoughts task or they were given no specific instructions.  Participants then completed a computer-based task which yielded chocolate rewards. 

The results showed that both the cravers and noncravers could suppress chocolate-related thoughts when instructed to do so.  Both groups of participants showed greater performance, and hence earned more chocolate, in the suppression than control condition.

A University of Califonia, Davis study says that the medicinal use of cacao, or chocolate, both as a primary remedy and as a vehicle to deliver other medicines, originated in the New World and diffused to Europe in the mid-1500s.  (Dillinger) These practices originated among the Olmec, Maya and Mexica. 

The word cacao is derived from Olmec and the subsequent Mayan languages; the chocolate-related term cacahuatl is Nahuatl , derived from Olmec/Mayan etymology.  Early colonial era documents included instructions for the medicinal use of cacao.  The Badianus Codex noted the use of cacao flowers to treat fatigue, whereas the Florentine Codex offered a prescription of cacao beans, maize and the herb tlacoxochitl to alleviate fever and panting of breath and to treat the faint of heart. 

Subsequent 16th to early 20th century manuscripts produced in Europe and New Spain revealed 100 medicinal uses for cacao/chocolate.  Three consistent roles can be identified:

  1. to treat emaciated patients to gain weight
  2. to stimulate nervous systems of apathetic, exhausted or feeble patients
  3. to improve digestion and elimination where cacao/chocolate countered the effects of stagnant or weak stomachs, stimulated kidneys and improved bowel function. 

Additional medical complaints treated with chocolate/cacao have included anemia, poor appetite, mental fatigue, poor breast milk production, consumption/tuberculosis, fever, gout, kidney stones, reduced longevity and poor sexual appetite/low virility. 

Chocolate paste was a medium used to administer drugs and to counter the taste of bitter pharmacological additives.  In addition to cacao beans, preparations of cacao bark, oil (cacao butter), leaves and flowers have been used to treat burns, bowel dysfunction, cuts and skin irritations. 


The Latest Research

A 2002 report from France shows that certain substances in cocoa powder inhibit 70 percent of cancer cells during a critical phase of their growth cycle.  Japanese researchers have shown that tiny amounts of a cacao bean extract are more toxic to human tumor cells than to normal cells. 

In some regards polycaphenol was even more effective than vitamin C.  Pretreatment of mice with polycaphenol also protected them from lethal E.  coli infections. 

In 2001, food researcher John Weisburger, PhD stated: "The cocoa bean, and tasty products derived from the cocoa bean such as chocolate, and the beverage cocoa, popular with many people worldwide, is rich in specific antioxidants.  " (Piotrowski, 2001)

The regular intake of such products, he continued, would increase the level of antioxidants, prevent the oxidation of "bad" LDL cholesterol, and probably prevent heart disease.  "It would seem reasonable to suggest inhibition of the several phases of the complex processes leading to cancer," Weisburger said.


Summary of Research

The recent findings on chocolate, including the presence of stearic acid in chocolate, do not make chocolate a health food.  Based on studies of isolated fatty acids, some scientists have found that stearic acid, unlike other saturated fatty acids, doesn't raise blood cholesterol. 

Stearic acid occurs combined with other fatty acids in our foods, however, and a recently published study doesn't support the notion that foods containing stearic acid are necessarily better for our hearts and arteries.  (Steinberg, 2000)

The present knowledge about antioxidants, how they interact, and what their presence in the diet as food and as supplements accomplishes, is limited.  Multiple studies have shown that people who consume diets rich in fruits and vegetables that contain antioxidants, but not other types of foods with antioxidants, have greater longevity.  There is at present no firm evidence that antioxidant supplements can decrease one's risk of developing cardiovascular disease. 

Some limited studies have suggested that antioxidant supplements can prevent heart disease or the aging process, but the results have been mixed, with some populations who took supplements even doing significantly worse than those that didn't.  (Steinberg, Bloom)

There are no explanations at present for these results.  A recently study with thousands of patients showed that a large Vitamin E supplement, a much-touted antioxidant, had no apparent effect on heart disease. 

Aside from the notion of good dietary fats and bad dietary fats, all fats, whether saturated, such as stearic or palmitic, monounsaturated or polyunsaturated, contain nine calories per gram.  If a person eats enough chocolate to get high amounts of either stearic acid or antioxidants, he/she will undoubtedly consume excess calories that will turn up as body fat. 

Obesity itself is a strong risk factor for several diseases, including heart disease.  In addition, most chocolate confections contain other ingredients that cannot be classified as heart-healthy.  In addition, behavioral studies show us that craving for a particular food is a learned activity and therefore can be unlearned.  (Rozin, 1991)


Chocolate: Behind Its Bad Rap

Chapter Three – Design of the Study


Design of the Study

There are several factors that were taken into consideration when designing the methodology for the study.  It is important to address the history of chocolate, the making of chocolate, the positive and negative effects of chocolate, who loves chocolate and why, and the nature of studies on chocolate.  By examining these things, the truth about chocolate unfolds.


The Difference Between Chocolates

Not all chocolates are alike, and not all chocolate candy will contain the procyanidins, flavonoids, and polyphenols that offer the beneficial properties. 

Cocoa beans found in the pods of the Theobroma cacao tree contain polyphenols, but those can be lost in some processing techniques. 

Mars has already addressed the issue by labeling certain products with a new trademark, 'Cocoapro.' According to the company's literature, this trademark is "a promise to the consumer that chocolate products from Mars Incorporated are made from cocoa beans that are specially handled to preserve their natural goodness." (Mars)


The chocolate connection

Still, none of these scientific findings would have come as much of a surprise to the indigenous peoples of Mesoamerica or early generations of Europeans.  (Young, 1994)

Culinary, medicinal, and ritual preparations of beans from the Theobroma cacao tree appear in numerous ancient texts.  Early physicians prescribed drinking or eating chocolate to add or restore flesh or weight gain to emaciated patients.

It was also used to stimulate the nervous system of feeble patients suffering from apathy or exhaustion.  Conversely it was dispensed to calm, soothe and tranquilize patients described as "over-stimulated," particularly those who suffered from strenuous labor or serious mental activity.  It has also often been used as a paste medium for administering drugs to counter the bitter taste of pharmacological additives.

Throughout the centuries, chocolate has been prescribed to:

Improve anemia
Awaken the appetite
Strengthen the brain
Increase breast milk production
Alleviate tuberculosis and gout
Cure kidney stones
Improve longevity
Enhance digestion
Invigorate kidney function
Improve elimination
Increase sexual appetite and virility
Stimulate nervous system of feeble patients
Calm, sooth and sedate over- stimulated patients
Add or restore flesh to emaciated patients


Today, traditional Mexican healers known as curanderos still prescribe it for bronchitis, and in rural Mesoamerica it is used as magical protection against snakebites and the stings of wasps, scorpions and bees.  Among the Mixteca Indians in Madera, Calif., it is drunk widely as a beverage and believed to be especially beneficial for school children.

Researchers in today's society are saying that chocolate:

Is a health food

Contaoins more antioxidents in chocolate than in fruit and vegetables

Contains compounds that promote heart health

Is flavonoid-rich, similar to green tea, red wine, olive oil

Has fat that contains stearic acid, oleic acid which decrease platelet activity

lowers cholesterol


Chocolate In Moderation

One of the major reasons that chocolate has gotten a bad rap throughout the years is because it is one of the favorite food of so many people.  People associate things that taste good with being nutritionally lacking and unhealthy.  (Coe)

However, according to a Hershey Foods Corporation-sponsored survey of registered dietitians (RDs), nearly all of the RDs surveyed believed that favorite foods should be incorporated into their clients' diets.  (Mustad, 2001)

The Hershey survey reported the following results:

The following Hershey's products are a good source of calcium (contain at least 10 percent of the Daily Value per serving):

Hershey's chocolate milk

Chocolate milk made with Hershey's syrup and milk

Hot cocoa made with milk, sugar and Hershey's cocoa

Hershey's drink boxes

In addition, chocolate milk is a good source of many nutrients.  Adding two tablespoons of Hershey's chocolate syrup to milk increases the calorie and carbohydrate content, not the fat.  Chocolate milk, made with 2% fat milk, has less fat than whole milk.

A sundae made with fat-free frozen yogurt, Hershey's chocolate syrup and whipped topping contains 180 calories and 2 grams of fat (3 percent of the Daily Value).

Most of the calories, fat and saturated fat in the American diet come from dairy, and baked grain products.  Five butter-flavored crackers (one serving) contain approximately 4 grams of fat.

Chocolate candy contributes less than 2 percent of total calories, fat and saturated fat in the American diet.  One serving of vanilla cookies (seven cookies) contains approximately 7 grams of fat.  Five mini-muffins (one serving) contain approximately 16 grams of fat.


History of Chocolate

Chocolate was first cultivated and consumed by the Mayans and Aztecs.  As early as 1000 A.D., cacoa beans were used as currency.  Perhaps as an excuse for enjoying chocolate treats, the Aztecs believed that drinking chocolate, which was the undiluted, unsweetened liquid from the fermented cacoa beans, would bring the drinker vast wisdom, understanding and energy.  Typically, chocolate was reserved for the ruling and priestly classes.  (Young)

Emperor Montezuma, who was said to have drank 50 or more portions daily, served chocolate to his Spanish guests in great golden goblets, claiming it was a food for the gods.

In 1492, on his journeys, Christopher Columbus was given several cacoa beans, which he took back to Spain.  However, he did not know how to ferment and process them.  In 1519, Cortez descended upon the Aztecs, destroying the armies and capital of Montezuma.  The Aztecs believed that Quetzacoatl had returned as prophesied and tried to get him to leave by plying him with chocolate.

This did not work.  Cortez organized the area as a Spanish colony and discovered how to process chocolate.  He then took the beans and his new information back to Spain.  The Spaniards added sugar and honey to the bitter liquid and loved the concoction. 

They reserved its use strictly for members of the court.  The Spanish succeeded in keeping the art of the cocoa industry a secret from the rest of Europe for nearly a hundred years.

When a Spanish princess married Louis XIII of France in 1615, she shared the secret of chocolate with him.  Soon, chocolate spread from Spain to France, England, Italy, Germany, Austria and Switzerland.  In 1753, Carolus Linnaeus named the tree Theobroma cacao, which meant "food of the gods, chocolate." (Young)

In 1755, the New World opened a chocolate processing house, which was the start of the company now known as Baker's Chocolate.


The Science of Chocolate

Cocoa butter is a triglyceride which starts to soften at 75 F., and melts at 97 F.  It is a highly saturated fat which consists of the fatty acid stearic acid, which is found in higher concentration in chocolate that in any other food.  (Bloom, 1998)

Stearic acid is rapidly converted by the liver into oleic acid, a monounsaturated that neither raises nor lowers serum cholesterol.  Oleic acid is also present in olive and canola oils. 

Chocolate does contain caffeine, but not a lot.  One ounce of milk chocolate usually contains 5 mg of caffeine, one ounce of semi-sweet usually has 5-10 mg, and a six-ounce cup of cocoa usually has 10 mg.  Comparitively, a six-ounce cup of coffee contains 100-150 mg.  Chocolate does not cause acne.  It does contain a protein that inhibits bacterial growth on teeth, and since it melts at body temperature and melts off one's teeth, the sugar in chocolate does not cling to one's teeth.

By this time, chocolate was an important food, especially for trade and was adored by most populations.  In fact, during World War II, the United States government valued chocolate's role in nutrition and in keeping the spirits of the military high so much that it allocated limited shipping space to import cacao beans.  (Coe)

Chocolate was included in the food rations of soldiers then, and continues to be included in the army's food rations today.  In addition, chocolate has been included in the nutrition packages taken to space by astronauts.


The Cacao Tree

Cocoa beans are the product of the cacao tree, whose origin is undetermined.  Many people say that the tree originated in the Amazon basin of Brazil, while others believe it was first seen in the Orinoco Valley of Venezuela or Central America.  Despite its origin, the cacao tree is a strictly tropical tree that thrives in hot, rainy climates, so its cultivation must be in lands less than 20 degrees north of the equator.  (Young)

Chocolate is harvested from the cacao tree that's native to the tropics of South America, and is now cultivated in a zone around the equator including Brazil, the West Indies, Venezuela, West Africa, Malaysia, and even Hawaii.  A cacao tree takes seven years to mature, then produces for about 20 years. 

The cacao tree is a sensitive and delicate tree, which needs protection from wind and requires a fairly shaded area to grow, particularly during its first two to four years of growth.  Newly planted trees are often shaded by different types of trees, such as banana, coconut or plantain trees. 

Once developed, cacao trees can grow in full sunlight, particularly if the soil conditions are fertile.  Cacao plantations are trees under cultivation, and must have even rainfall and rich, drained soil to flourish.

Large plantation methods of growing include heavy doses of pesticides and fertilizers, and have resulted in losses of huge expanses of cacao trees from disease and pests.  Small farms, which grow cacao under the shade of taller rain forest trees, are better able to grow the trees organically.  They use fewer pesticides and produce trees better able to resist the spread of disease and pests.

Most cacao trees will begin bearing fruit in their fifth year.  The fruit, which will be converted into chocolate and cocoa, grows from the trees as green, gold or maroon colored pods.  While the tree will bear fruit year-round, harvesting is seasonal. 

There are three classifications of pods from cacao trees.  Criollo, which is the best type, is a soft pod with a light, pleasant aroma.  Forastero, a more plentiful pod, is a thick pod with a pungent aroma.  Trinitario, which is said to be a cross of both criollo and forastero, has many characteristics and a good, aromatic scent.

In the Western hemisphere, plantations normally consist of all classifications of cacao beans.  Recently, cacao growers have turned increasingly to hybridization as a means of improving the quality of the bean and making it more disease resistant.  Scientists using state-of-the-art biotechnology techniques are also trying to improve the quality of cacao and its resistance to disease.


Processing Chocolate

Cleaning is the first step to manufacturing chocolate.  The cacao beans are passed through a cleaning machine that removes dried cacao pulp, pieces of pod and other extraneous material.  When cleaned, the beans are weighed and blended according to a company's specific requirements.  The science of making chocolate depends on the ability to create the right formula for the desired end product through the proper selection of available beans.  (Young)

The beans are then roasted in large rotary cylinders to bring out the aroma of the chocolate.  Roasting can last from 30 minutes to two hours at temperatures upward of 250 F.  As the beans roast, the moisture content drops and their color changes to a rich brown, and their aroma is formed.

After roasting, the beans are cooled and their thin shells, which are brittle from roasting, are taken off, leaving the "nibs." The nibs are made of about 53 percent cocoa butter.  These nibs are crushed between grinding stones, which generates enough frictional heat to liquefy the cocoa butter and form what is commercially know as chocolate liquor.  The term liquor refers to liquid, as opposed to alcohol.  When this liquid is poured into molds, unsweetened or bitter chocolate is formed.

Up until now, the processes of making chocolate and cocoa have been identical.  The process now changes.  However, it should be noted that the by-product of cocoa shortly becomes an essential ingredient of chocolate.  That ingredient is the unique vegetable fat, cocoa butter, which forms about 25 percent of the weight of most chocolate bars.


Making Cocoa Powder

The chocolate liquor, which later becomes cocoa, is manufactured through giant hydraulic presses weighing up to 25 tons, where pressure is applied to remove the cocoa butter.  The fat is drained away through metallic screens and is then collected for use in chocolate manufacturing.  (Bloom)

Cocoa butter is an important product of the chocolate industry.  It is unique among vegetable fats because it is a solid at normal room temperature and melts at 89 to 93 F., which is a little less than body temperature.  Its success in resisting oxidation and rancidity makes it very practical.  Under normal storage conditions, cocoa butter can be kept for years without spoiling.

The pressed cake that is left after the removal of cocoa butter can be cooled, pulverized and sifted into cocoa powder.  Cocoa that is packaged for sale to grocery stores or put into bulk for use as a flavor by dairies, bakeries, and confectionery manufacturers, may have 10 percent or more cocoa butter content.  "Breakfast cocoa," a less common type, must contain at least 22 percent cocoa butter.

In the so-called "Dutch" process, the manufacturer treats the cocoa with an alkali to develop a slightly different flavor and give the cocoa a darker appearance characteristic of the Dutch type.  The alkali acts as a processing agent rather than as a flavor ingredient.


Making Chocolate

While cocoa is made by removing some of the cocoa butter, chocolate is made by adding it.  All eating chocolate, whether dark, bittersweet or milk, is made this way.  The cocoa butter is added to enhance the flavor and make the chocolate more fluid.  (Bloom, Young)

One example of eating chocolate is sweet chocolate, a combination of unsweetened chocolate, sugar, cocoa butter and vanilla.  It is made by melting and combining the ingredients in a large mixing machine until the mixture has the consistency of dough.

Milk chocolate, the most common form of all chocolates, goes through essentially the same mixing process-except that it involves using less unsweetened chocolate and adding milk.

The ingredients are then passed through a series of heavy rollers, refining the mixture to a smooth paste that is ready for conching, a flavor development process that kneads the chocolate. 

After the conching process, the mixture follows a series of interval-heating, cooling and reheating-and then at last into molds to be formed into the shape of the complete product.  The molds take a variety of shapes and sizes, from the popular individual-size bars available to consumers to a ten-pound block used by confectionery manufacturers.

When the molded chocolate reaches the cooling chamber, cooling proceeds at a fixed rate that keeps hard-earned flavor intact.  The bars are then removed from the molds and passed along to wrapping machines to be packed for shipment to distributors, confectioners and others throughout the country.

For convenience, chocolate is frequently shipped in a liquid state when intended for use by other food manufacturers.  Whether solid or liquid, it provides candy, cookie, and ice cream manufacturers with the most popular flavor for their products.  Additionally, a portion of the United State's total chocolate output goes into coatings, powders and flavorings that add zest to our foods in a thousand different ways.


Different Types of Chocolate

It has been a common misconception for many years that chocolate is a bad food, particularly because it was believed to be a source of saturated fats, which can have a very negative effect on one's overall health.  But recent studies revealed that the fat in chocolate is actually stearic acid, which does not have the same harmful effects.  Instead, it is a fat that the body changes, through a series of biochemical reactions, into oleic acid.  (Waterhouse)

Most studies generalize chocolate, failing to provide specific details about how much and what type of chocolates are involved in the studies.  It is important to distinguish different types of chocolate to determine which ones have the most nutritional and psychological benefits. 

Rich, dark chocolate usually contains about 70 percent of cocoa, which is an important source of antioxidants, but milk chocolate contains mostly fats, sugar and vegetable oils.  Many of the studies that show the benefits of chocolate are reviewing dark chocolate.

The bottom line is that just because chocolate tastes good does not mean that it is unhealthy.  But researchers need to stress the importance of a healthy, balanced diet when promoting the positive aspects of chocolate, as well as the negative effects of what is added to chocolate, and differences between types of chocolate.

Cocoa powder is the residue left over after the cocoa butter has been pressed from the ground, roasted beans.  Unsweetened cocoa powder is often used for baking purposes.  (Bloom)

Milk or eating chocolate is typically used for eating, rather than baking, because of its delicious taste and added sugar and condensed or powdered milk.  The proportion of dairy fat in this type of chocolate has a lower melting point and is softer than cocoa butter, which results in the softer texture of the chocolate.

Plain or cooking chocolate is pleasant-tasting because of its sugar content.  It has varied amounts of cocoa butter and is often used for cooking.

Unsweetened chocolate has a high amount of cocoa butter, which makes it perfect for baking.

White chocolate is creamy in color and texture because it does not have any cocoa solids.  However, it does contain cocoa butter, sugar and milk solids.  It does not set as firmly as milk and dark chocolate.  Also called dipping or coating chocolate, couverture comes in dark, milk and white options.  The dark type comes in varying degrees of bitterness, from sweet through to extra bitter, depending on the amounts of cocoa solids and sugar added.



Theobromine occurs naturally in cocoa beans and is present in all chocolate products.  The amount of theobromine in the finished product depends on the type of chocolate used and the serving size.  Milk chocolate contains less theobromine than semi-sweet or dark chocolate.  Theobromine has a mild diuretic action (increases urine production) similar to caffeine, but does not stimulate the central nervous system like caffeine.  (Bloom)

A study in 1994 investigated chocolate craving by administration to male and female cravers of either milk chocolate, white chocolate, which lacks cocoa and its bioactive agents, cocoa capsules, which contain bioactive agents minus sensory properties, or placebo capsules.  Results showed higher consumer preference for white chocolate than cocoa capsules and demonstrated that only milk chocolate fully satisfied cravings.  (Coe)

These results suggest that, rather than pharmacological effects, chocolate craving is due to its energy content and sensory properties, such as aroma, sweetness and texture, and to psychological associations with chocolate.  Still, feelings of craving may be intensified by bioactive agents and it is possible that the efficacy of sensory properties in satisfying cravings may be due to conditioning by a pharmacological effect.

The darker the chocolate, the better it is for you, according to Prof.  Joe Vinson of the University of Scranton.  Weight for weight, he said, milk chocolate has twice as many antioxidants as blueberries and dark chocolate has five times as many.  And cocoa powder contains twice as much antioxidants as dark chocolate and is almost devoid of fat.  (Bloom)

Although milk chocolate contains some cholesterol-raising milkfat, the cocoa butter in dark chocolate does not.  Unlike other saturated fats, which are known to raise blood cholesterol levels, the saturated fat in cocoa butter is mostly stearic acid, wand has a neutral effect on cholesterol levels.  In fact, 76 percent of the fat in cocoa butter is made of heart healthy unsaturated fats or neutral fats.  In addition, the cocoa butter is vegetable fat, so it has no cholesterol.

A Dutch study reported recently that dark chocolate contains substantial amounts of beneficial flavonoids.  Flavonoids, which are compounds commonly found in tea, may have protective effects against cancer and heart disease. 

A one-ounce piece of dark chocolate has about as much of these compounds as a half cup of black tea.  In a recent study at Tufts University, researchers that measured the anti-oxidant power of foods found that cocoa powder had more than green tea and blueberries.

Chocolate has been shown to enhance moods.  Some researchers say that this is more likely the result of how good it tastes than because of any compounds in the chocolate itself.  Researchers agree that chocolate contains small amounts of cannaboids, which are the chemicals that are in the same family as marijuana, and stimulants like theobromine, phenylethylamine, and caffeine; but some say you would have to eat a huge amount, about 25 pounds, to have a noticeable effect.


Nutrient Content of Milk Chocolate

Nutritional information on chocolate and the %RDA provided to you in a single serving.




% French Equiv

Australia and New Zealand

Energy (kcal)





Carbohydrate (g)





Fiber (g)





Protein (g)





Fat (g)





Saturated (g)





--Monounsaturated (g)





--Polyunsaturated (g)





Cholesterol (mg)





Sodium (mg)





Potassium (mg)





Calcium (mg)





Phosphorus (mg)





Magnesium (mg)





Iron (mg)





Zinc (mg)





Copper (mg)





**All Ranges taken from USDA Estimated Safe and Adequate Daily Dietary Intakes of Trace Elements


Nutrient Content of Semisweet Chocolate (Dark Chocolate)

Nutritional information on chocolate and the %RDA provided to you in a single serving.



% RDA (a)

% French Equiv (b)

Australia and New Zealand (c)

Energy (kcal)





Carbohydrate (g)





--Fiber (g)





Protein (g)





Fat (g)





--Saturated (g)





--Monounsaturated (g)





--Polyunsaturated (g)





Cholesterol (mg)





Sodium (mg)





Potassium (mg)





Calcium (mg)





Phosphorus (mg)










Iron (mg)





Zinc (mg)





Copper (mg)


10-20% *



**All Ranges taken from USDA Estimated Safe and Adequate Daily Dietary Intakes of Trace Elements


Value of Chocolate

Most studies show that cravings for chocolate are both biological and psychological.  (Bloom)

Because chocolate derives about 50 percent of its calories from chocolate, it boosts serotonin levels in the brain.  About half of its calories are derived from fat, so it can also boost brain endorphin levels.  This results in a powerful effect in which all brain chemicals are positioned at optimal levels for positive moods and increased energy.

In addition, chocolate contains many other compounds that have positive effects on brain functions.  Chocolate contains phenylethylamine, a chemical that is released in the brain when in love.  Whether it is the same exact chemical has not been proven but chocolate provides a euphoric feeling for many.

It also contains theobromine, a chemical similar to caffeine that affects the brain by increasing alertness, cognitive functioning and concentration.  The addition of magnesium to chocolate affects the brain by manufacturing seratonin and stabilizes one's mood.

Chocolate is the only food that combines all of these ingredients and possibly some other brain-pleasing ingredients that have yet to be discovered.  Chocolate can cause a rush of both seratonin and endorphins to the brain cells, resulting in optimal brain happiness.  (Waterhouse)

Psychologically, chocolate provides a beneficial experience for those who eat it, as well.  Due to the fact that chocolate has a melting point of 97 degrees, just below body temperature, it melts immediately and provides flavorful bursts for the taste buds like no other candy can.

It has a blend of over 500 flavors, which is more than any other food, so it has enhanced sensory properties.  Also, people revert back to childhood memories when chocolate was provided as a treat, so they associate the candy with a reward.  Chocolate also continues to be one of the most frequently given gifts to show love, appreciation and thanks.


Contents of Cocoa (Bitter Chocolate)

55% of fat. 

12.8% of protein. 

Provides 455 calories/100 gr. 

Rich in minerals, such as phosphorous, calcium, copper, potassium, iron, sodium, magnesium, iodine and molibdene.

Rich in vitamins: A, B, C, D, E, Nitacine K, B1 and B2.

Contains 6 aminoacids essential for one´s health. 

Has low content of saturated fats and thus, stimulates the good cholesterol and counterattacks the bad one; are easily absorbed and do are not deposited in the arteries.

** USDA Estimated Safe and Adequate Daily Dietary Intakes of Trace Elements, 2001.  Mars.


Negative Effects of Chocolate

Chocolate may also have some negative effects, particularly in migraine sufferers and among women with severe PMS.  It may increase kidney stone formation in those who are prone to that painful disease.  For people with diabetes it poses another problem, it also has sugars and carbohydrates that can have negative effects.  (Kurzer, 1997)

There are compounds in chocolate -the methylxanthines and fat - which can trigger heartburn.  Chocolate can relax the opening between the stomach and the esophagus, allowing stomach acid to back up.

Even though chocolate has been proven to not affect cholesterol directly, fat grams in chocolate, the human body gains weight from an excess of calories and extra pounds can raise cholesterol levels.

Also, nutritionists warn against substituting chocolate for healthy foods.  While the health benefits of fruits and vegetables are firmly established, it is not proven that the phenols in chocolate actually lower heart-disease risk.


Women and Chocolate

Recent studies have led to an interesting about women and chocolate, prompting several books on the subject, including, "Why Women Need Chocolate." The book's author, Debra Waterhouse, a nutritionist, surveyed hundreds of women for her survey, finding that 97 percent of all women surveyed reported food craving, 68 percent of which were for chocolate.  (Waterhouse, 2000)

Fifty percent of these women said that they prefer chocolate to sex.  Women were 22 times more likely than men to choose chocolate as a mood enhancer.  And the majority of the $3.4 million spent on chocolate each year is spent by women. 

Countless surveys and papers have been written on women and chocolate, revealing that it is the number-one craving for women.  Studies show that women crave the physical elements of chocolate that induce a pleasurable biological experience, such as sugar, fat and phenylethylamine.

When the Aztecs first discovered chocolate, they forbade women to consume it because it was considered an aphrodisiac. 

The remarkable effect of chocolate on the brain has prompted many researchers to label it as a non-drug anti-depressant, the ultimate de-PMSer or the Prozac of plants. 

A recent survey compared the response of men and women when asked about their feelings about chocolate.


Typical male responses were:

It's okay.

I could take it or leave it.

I really don't care for it.

It's good to eat.

Once in a while, I enjoy it.

Real men don't eat chocolate.


Typical female responses were:

It's ecstasy.

It's delicious and divine.


A necessity of life.

Woman does not live by bread alone, maybe chocolate.

It's second only to sex.

It's better than sex.

It makes me feel good all over.

Many women crave certain foods, especially chocolate.  Chocolate and other foods contain naturally occurring substances which are thought to affect neurotransmitters and, as a result, mood.  Consequently, reports of dietary treatments for premenstrual syndrome, depression and the elimination of food cravings fill the popular media.  (Waterhouse, Kurzer)

Critical evaluation of the scientific literature that forms the basis of these reports shows inconsistent results.  One hypothesis is that food cravings exist as a way to correct a biological need, such as a nutrient deficiency or a mood disorder. 

If this were the case, other foods containing the nutrient or "bioactive" substance should satisfy the craving.  (Kurzer) However, few individuals find that substitute foods will satisfy their needs.  For example, chocolate contains relatively high amounts of the nutrient magnesium and the bioactive substance phenylethylamine.  But chocolate cravers do not seek other foods high in these substances to satisfy their love of chocolate.


Chocolate and Pets

Many people have expressed concern about the harmful effects of chocolate because of its adverse effects on animals, such as rats and dogs.  It is important to understand which ingredients in chocolate are toxic to species that are susceptible to chocolate poisoning. 

It is the theobromine in chocolate that, in large amounts, has negative effects, relaxes smooth muscles and stimulates the heart and nervous system.  While chocolate has small amounts of caffeine, which has a harsh effect on the nervous system, it does not contain enough caffeine to harm an animal.  It has been proven that while chocolate can be toxic to certain species in large amounts, it is not likely to poison an animal in moderate amounts.  (Edmundson)


Chocolate: Behind Its Bad Rap

Chapter Four – Results and Findings


Results and Findings

Chocolate has been praised for its nutritional and psychological values for centuries.  World War II soldiers took advantage of its high nutritional content and shelf stability, while athletes and astronauts use it for its high fat and carbohydrate contents, which are known to boost energy levels.  (Young)

A 15 oz bar of milk chocolate provides 9% of the Recommended Daily Allowance (RDA) for calcium, 3% for iron, 6% for protein, 9% for riboflavin, 1.9% for thiamin and 2.4% for vitamin A.  Chocolate is also particularly rich in magnesium, and has a high calorie content due to its considerable contents of fat and sugar.

Surveys and reports say that cravings for chocolate have been observed in approximately 40 percent of women and 15 percent of men.  Many females report that their cravings occur mostly during the start of menstruation.  Additional reports show that chocolate is used as a self-medication for depression syndromes, which indicates a physiological basis for cravings influenced by hormone levels and mood.  (Kurzer)

More than half of chocolate cravers say that there is no substitute for their craving for chocolate and women with PMS claim that they increase consumption of chocolate during this time.  This shows that there are carbohydrate and bioactive agents in chocolate.  Magnesium has also been shown to contribute to chocolate cravings since cravings for chocolate have been reduced by magnesium supplements.

In addition to the many nutritional benefits of chocolate, the fat and carbohydrate ingredients of chocolate add to its sweetness and texture.  These sensory properties provide consumers of chocolate products with comforting qualities.  It is apparent that the high fat content of chocolate provides energy and satisfactory feelings, while the high sugar content improves energy and feelings of happiness.  Reports of increased brain tryptophan levels and serotonin synthesis with carbohydrate consumption may account for enhanced feelings of well being, as well.

Chocolate is limited in its use as a functional food due to its high sugar and fat contents; however, cocoa contains the functional constituents of chocolate with no sugar and very little fat.  Since cocoa is already used as a colorant and flavouring, it is already licensed for use as a food additive and does not require expensive food safety trials, unlike other potential functional ingredients.  (Waterhouse)

Cocoa is currently under investigation for potential functional properties as an antioxidant, while in the highly developed Japanese functional food market, chocolate products are already being marketed for their antioxidative properties.  It is possible that, in the future, cocoa and chocolate may once again be regarded as medicinal products rather than luxury foods, and chocolate products may be consumed for their health-promoting as well as comforting properties.

It should be noted that an improvement in cardiac risk factors does not automatically translate into a reduction in heart-disease risk.  By analogy, even though taking estrogen reduces serum cholesterol levels, it does not reduce the risk of having a heart attack.  In addition, the theoretical benefits of eating chocolate must be balanced with the potential risks. 

Most chocolate products are high in fat, sugar, and calories, and consuming excessive amounts of chocolate could promote obesity, which might actually increase the risk of heart disease.  Chocolate contains a number of different chemicals that can affect the brain and nervous system.  In addition to relatively large amounts of theobromine (a compound similar to caffeine), chocolate contains phenylethylamine (which has actions similar to those of amphetamines) and a recently discovered molecule called anandamide (which binds to the same site in the brain as does the active ingredient in marijuana). 

The effects of these compounds on human health are not entirely clear; however, chocolate does appear to be a "mind-altering" food, with potentially negative implications for some people.  In addition, chocolate can be addicting, as the many people who crave it will attest.  (Rozin)


Chocolate: Behind Its Bad Rap

Chapter Five – Conclusions, Implications and Recommendations


Conclusions, Implications, and Recommendations

Although research and information on health benefits of chocolate is surfacing, it's important to remember that chocolate is at the tip of the food guide pyramid along with fats, oils and sweets.  When we eat too many calories and fat, we gain weight, which increases risk for heart disease, some cancers, diabetes, obesity and other diseases.  Eating a chocolate bar will not necessarily make you fat, but chocolate treats should be balanced with other food choices throughout the day.  So have your chocolate and eat it too.

While there are definite positive and negative effects associated with chocolate consumption, the researchers who conducted the study believe that chocolate is a useful addition to the diet.  While the research as to whether or not chocolate should be used to treat a variety of cardiovascular conditions is still somewhat inconclusive, chocolate may be helpful in many situations.

Chocolate's bad reputation comes from the many myths surrounding it.  (Edmondson) Despite popular belief, chocolate doesn't cause or worsen acne.  Neither does it cause dental decay.  In fact, chocolate has certain properties that work against sugar's natural tendency to produce the oral bacteria that leads to decay.  People are also afraid of chocolate's caffeine content but it is surprising to know that while coffee has 130-150 mg of caffeine, chocolate only has 6 mg per ounce.

Throughout history, chocolate has provided many benefits to many groups of people but still gained a bad reputation as an unhealthy food.  The Spaniards considered chocolate to be an aphrodisiac and the Europeans used it for medicinal purposes.  Today, efforts are being made to disprove the myth that chocolate contains a magical ingredient, instead attributing the pleasant feelings associated with chocolate to a psychological association with the texture.  Studies have proven that chocolate stimulates the brain to release natural "painkillers." (Young)

Many research projects have uncovered a variety of conclusions regarding the positive effects of chocolate, ranging from benefits of the heart to psychological treatment.  Whatever the reason, the short-term effect of chocolate is undisputed.  And researchers are chipping away at chocolate's bad reputation as a junk food with their continued findings.  One of the most important studies showed that chocolate's source of saturated fat was stearic acid, which does not raise cholesterol levels.  Perhaps if the Food and Drug Administration reclassified stearic acid as less harmful, the nutritional value of chocolate would rise.

It is important to recognize that many of the studies discussed in this paper are incomplete or meager.  Many others, especially those sponsored by chocolate companies, can be misleading and leave a lot of significant information out.  For example, while research stresses that chocolate contains polyphenols, which have antioxidant properties, this cannot be a reason to label chocolate as a health food.  Higher antioxidant benefits can be reached by eating fruit and vegetables, which also provide more vitamins and nutrients.

The majority of studies finding health value in chocolate are funded by chocolate manufacturing companies, such as Hershey's and Nestle.  This trend is likely to continue because biased sources generally contribute the most money because of the possibilities of personal gain.  For this reason, it is extremely important that the process of peer review and scientific scrutiny be followed carefully.

Still, while we wait for updated research, there are many known facts about chocolate that should take away the guilty feelings associated with it.  Chocolate is nutritious and this makes chocolate a must for ration packs in the army, for trampers/hikers, mountain climbers. 

Chocolate contains protein, fat, carbohydrate, calcium, magnesium, iron, zinc, carotene, vitamin B1, B2, B3, B6, B12, and folate.  Milk chocolate contains a higher percentage of these than dark chocolate but it does depend on the levels of cacao solids and the brand of chocolate analyzed.  It is easy to see why chocolate is an energy food and can be beneficial to the diet when eaten in moderation.  (USDA)

Chocolate is often called natures' Prozac.  Its brain pleasing qualities are provided by its sugars, fats, PEA, theobromine, magnesium.  It is possible that more brain pleasing ingredients have yet to be discovered.  If taken in moderation, it is one of the most natural anti-depressants out there.

Most of the positive statements about chocolate come from "test tube" research and not from research done on humans.  Since the studies are funded by those interested in making money from increased sales of chocolate, the studies could be biased or compromised to some degree.  (Steinberg)

The next step would be to increase research on chocolate that shows the results and proof of nutrients going into the body on a cellular level.  The cellular level is where change takes place, not just on a slide or in a test tube in a lab.  Scientists know that just because a food contains nutrients does not mean that the human body will absorb these nutrients in a positive way.

The studies should also differentiate between the ingredients contained by different types and brands of chocolate.  Depending on the quality and brand of chocolate, the percentage of cacao butter will vary and this is an important change.  Many chocolate companies do not have the resources or are not willing to spend the money to use high amounts of cacao butter.  It is expensive and often substituted with cheap fat.  In regards to this issue, Carl Keen has said, "look at the total fat intake that occurs in one day, and then start making decisions as to which foods with fat you are going to eat, based on what else the food brings with it."

While chocolate has been praised for not raising LDL, the bad cholesterol, critics say that most of the research done to prove this does not provide enough information to undoubtedly say that the research hasn't missed an important difference. 

For example, a more recent, larger and non-industry-funded piece of research showed results of 80,082 nurses that filled out dietary surveys, from which researchers could figure out how much of this or that fatty acid was being consumed. 

The nurses were followed for more than 14 years for outcome measures, not laboratory values like LDL, but statistics like heart attacks and deaths.  These things happened more often in the high stearic-acid-eating group.  One of the most harmful products in the stearic acid category is beef tallow, which contains nearly as much stearic acid as cocoa butter. 

This creates a loophole.  On one hand, studies show that chocolate probably won't raise your cholesterol.  But the studies were considered weak and biased.  On the other hand, a long-term population study reveals that cocoa butter's main fatty component can lead to heart attacks.  But this study doesn't actually look at cocoa butter itself.

These studies show conflicting results, which indicates the need for further research and outside funding.


Bruinsma K, Taren DL.  Chocolate: Food or Drug? University of Arizona, 1999.

Marcus DA, Scharff L, Turk D, Gourley LM.  Double-blind provocative study of chocolate as a trigger of headache.  University of Pittsburgh, 1997.

Small, Dana.  Measuring Brain Activity In People Eating Chocolate Offers New Clues About How The Body Becomes Addicted.  Northwestern University, 2001.

Tytgat J, Van Boven M, Daenens P.  Cannabinoid mimics in chocolate utilized as an argument in court.  Laboratory of Toxicology, 2000.

Johnston L, Bulik CM, Anstiss V.  Suppressing thoughts about chocolate.  University of Canterbury, 1999.

Dillinger TL, Barriga P, Escarcega S, Jimenez M, Salazar Lowe D, Grivetti LE.  Food of the gods: cure for humanity? Department of Nutrition, University of California, Davis, 2000.

Bloom, Carole.  All About Chocolate: The Ultimate Resource to the World's Favorite Food.  IDG Books Worldwide, 1998.

Speak Out, 2001 Healthy Living Survey.  Speak Out, 2001.

Waterhouse, Debra.  Why Women Need Chocolate, 2000.

Coe, Sophia.  The True History of Chocolate.  Thames & Hudson, 1996.

Young, Allen.  The Chocolate Tree: A Natural History of Cacao.  Smithsonian Institution Press, 1994.

USDA Estimated Safe and Adequate Daily Dietary Intakes of Trace Elements, 2001.

Vinson, Wan, Etherson, JA, et al.  Effects of cocoa powder and dark chocolate on LDL oxidative susceptibility and prostaglandin concentrations in humans.  Clinical Nutrition, 2001.

American Heritage Dictionary of the English Language, The, Fourth Edition.  Houghton Mifflin Company, 2001.

Steinberg, Fredric.  Chocolate: Good or Bad? American Council on Science and Health, 2001.

Mustad, VA; Kris-Etherton, PM.  Topics in Food and Safety, Hershey Foods Corporation, 2001.

Piotrowski, Leslie.  For the Love of Chocolate: Melting the Myths.  Mars, Inc., 2001.

Rozin, P.; Levine, E.; and Stoess, C.  Chocolate Craving and Liking.  2001.

Edmondson, M.  Research disputes confectionery myths.  Candy Industry, 1996.

Kurzer, M.  S.  (1997) Women, Food and Mood.  Nutrition Reviews, 1999.

Mars Web Site,, 2002.
thesis helpDissertation Help
dissertationAvoid Foreign Sites
dissertationWhy Choose Us?
dissertationAsk a Question
thesis help10% Discount
thesis helpInstallment Plan
dissertationWriting Features
Place an Order
thesis helpGuarantee
thesis helpNever Resold
thesis helpPayment Options
thesis helpTopics
thesis helpNovels
thesis helpPrivacy

dissertation sample

dissertation sample

Sample Dissertation © 2002-2022   All rights reserved.

Our dissertation help and thesis writing enable customers to learn how to research and write their own essays,
term papers, dissertations, thesis papers, and research proposals, and they are responsible for citing us as a reference source.