Cocoa and Chocolate: Health Benefits, Myths, and Science

Introduction: Chocolate in Diet and Society

Pacemakers and vitamin pills are just two of the millions of health products sold daily around the world. But one of the most easily accessible health-relevant foods is right beneath our noses: chocolate. Cocoa, the plant from which chocolate is derived, has had a positive effect on today's society because of its active role in daily health.

Many people believe that chocolate is bad for you — that its calories outweigh its positive health benefits. Urban legends and common misconceptions concerning the use of chocolate have been rampant for hundreds of years: that it causes acne, retardation, or even blindness. All of these accusations are baseless, and, as this paper will show, the evidence points in the opposite direction.

As chocolate is a prominent player in the modern diet, it is important to understand its health dimensions. Diet is what we take into our bodies — what we run on. When we eat healthy food we perform better and are more productive. When we eat poorly we are slow, sick, and unproductive. Every aspect of diet should be analyzed to allow us to live up to our potential.

Cocoa goes a step further than simple nutrition. Not only does it provide energy, it supplies chemicals that influence our personalities and moods. Modern psychology holds that every thought is simultaneously a biological reaction — a chemical process within the brain. Our thoughts and chemical states can determine how we feel, our motivation, and our goals. What we take into our bodies is therefore of the utmost importance, because our diets help shape our thought processes, which in turn shape our moods and actions.

The Cacao Tree and Cocoa Bean Composition

It is a commonly held belief that chocolate, as a sweet, is something you would be better off without (Feldman, 1998). Further evidence presented in this paper demonstrates that chocolate, in moderate doses, can actually improve quality of life in several respects through the chemicals it prompts the brain to release.

The Theobroma cacao tree has been present throughout human history for at least four thousand years, cultivated for the past ten centuries. It is indigenous to tropical Central and South America, originating in the rain forests of the Amazon or Orinoco basin before spreading to Mexico and Costa Rica. Today, cocoa is cultivated across the globe — in the West Indies, Brazil, Venezuela, West Africa (Ghana, the Ivory Coast, and Nigeria), Madagascar, Sri Lanka, the Philippines, Malaysia, and even in the United States.

Originally, the Aztecs called cocoa xocoatl, meaning "bitter drink." That term was eventually integrated into the modern word "chocolate." At the height of Aztec civilization, 100 cocoa beans held the value of an entire slave — a testament to how powerfully the natives regarded the plant. They used cocoa in religious ceremonies, for calculations, and across countless other applications.

When Cortés delivered beans to the Spanish emperor between 1502 and 1528, cocoa took on a new form — a beverage. Sugar and cinnamon were added to create exciting new flavors, and the mixture was heated to improve upon the otherwise bitter Aztec drink. Spain kept the recipe secret for many years before introducing it to France in 1657. England and its colonies soon followed. Baker founded his Massachusetts chocolate factory in 1765, marking the beginning of chocolate's influence on American culture.

The cocoa tree takes a full seven years to ripen and then continues to produce for twenty years. The seeds, or beans, are bitter because of their alkaloid (methylxanthine) content, and fermentation is necessary to develop the characteristic chocolate flavor. The cocoa bean is approximately 31% fat, 14% carbohydrate, and 9% protein. It is rich in the amino acids tryptophan, phenylalanine, and tyrosine, which are precursors to norepinephrine and dopamine.

Making and Eating Chocolate

The 400 chemicals identified in the cocoa bean include polyphenols (6%) — among them pyrazines, quinoxalines, oxazolines, pyrroles (tannins), pyridines, and the flavonol proanthocyanidin — as well as the amphetamine-like phenylethylamine, the methylxanthines theobromine (2%) and caffeine (1%), and 2% salts and 1% acids. Similar chemicals are found in red wine, grapes, tea, onions, apples, and citrus fruits. Consumption of these chemicals has been associated with a decreased risk of cardiovascular disease and certain cancers.

A cocoa tree yields 50 to 60 pods. The ripe, melon-like pods are cut by hand and each contains 20 to 40 seeds, which are also removed by hand. The beans ferment under the sun for 4 to 6 days, then are dried for 5 to 7 days. The dried beans are roasted for 40 minutes at temperatures between 100°C and 220°C to enhance flavor. The shell is removed to yield the cocoa nib, which is then milled by a mechanized process introduced during the Industrial Revolution — the development that made widespread distribution of chocolate possible, transforming it from a noble delicacy into a common treat.

The end product of milling is solid and bitter. "Pressing," a process invented by the Dutch chemist Van Houten in 1828, separates the 45% cocoa solids or flaky cocoa powder (containing 17% fat, 2.6% theobromine, and 0.2% caffeine) from the remaining 55% golden, stable cocoa butter. This separation allowed the addition of ingredients such as fruits and nuts. In 1831, chocolate became available in the United States. Hershey began business around 1900. Sugar and dry milk solids were added to cocoa solids to produce milk chocolate in the Swiss process introduced by Nestlé in 1875. "Roller refining" of chocolate for 72 hours reduced particle size to a premium 10–12 micrometers. Tempering controls crystal formation, and extra cocoa butter can be added using a stirring or "conching" process introduced by Lindt, which improves smoothness and melting. Alkali is generally added to cocoa to increase solubility and neutralize acids, producing a milder flavor.

The FDA regulates the types of chocolate within U.S. borders. Current types include: bitter (chocolate liquor to which vanilla may be added); bittersweet (35% chocolate liquor with cocoa butter and sugar, and semisweet/chips also at 35% chocolate liquor and 27% cocoa butter); sweet chocolate (15% chocolate liquor); and milk chocolate (Swiss, with 10% chocolate liquor, 12% milk solids, condensed or whole milk, and 3% milk fat). White chocolate does not contain cocoa powder or its associated chemicals. To be defined as chocolate, a product must contain materials from the cocoa bean, to which sugar and milk may be added, and must use only cocoa butter and a small amount of dairy butter as its fat source.

Chocolate is consumed primarily as a cocoa beverage or incorporated into confections, candies, desserts, and snacks. Chocolate syrup, mousses, puddings, and baked goods may also contain butterfat or other saturated fats (such as tropical vegetable oils), so reading labels carefully is important.

The United States leads the world in the import and production of chocolate candy, with the population consuming on average 10 lb of products per person per year, approximately one-third of which is chocolate. The highest percentage of consumption occurs among 16- to 19-year-olds and women between 40 and 49 years of age. Most of this chocolate is not eaten in solid form but as "panned, enrobed, or molded" chocolate — candies and coatings, for example. The Swiss consume an average of 22 lb of chocolate products per person per year, though they also invented milk chocolate.

Chocolate as a Fat and Its Effects on Blood Lipids

Chocolate intake accounts for only about 1% of total fat intake in the United States, according to data from the 1987–1988 National Food Consumption Survey. By comparison, 30% of dietary fat comes from meats, 22% from grains (in crackers, cookies, cakes, and pies), and 20% from milk and dairy products. The fat in chocolate, cocoa butter, is high in saturated fat (60%), half of which is stearic acid. Cocoa butter contains more stearate than any other common fat or oil, yet as a vegetable fat it does not contain cholesterol. Milk chocolate, which contains added milk fat, is therefore a source of cholesterol. Among common fats and oils ranked by saturated fat content, palm kernel and coconut oils rank highest, with cocoa butter in third place. When ranked by content of long-chain saturated fatty acids of 12 to 16 carbon chain length, cocoa butter drops to sixth place, below palm oil, butter oil, and beef tallow. Chocolate, especially higher-fat varieties, is a high-calorie food: a 3-lb box of chocolates yields 6,900 kcal.

In controlled feeding trials in humans, cocoa butter results in significantly lower levels of serum total and low-density lipoprotein (LDL) cholesterol compared with butter or beef fat, though it is not as hypolipidemic as olive oil. Stearic acid is termed a "neutral" fatty acid with respect to raising serum or LDL cholesterol. This lack of effect is due in part to its poorer digestibility and lesser absorption compared to other long-chain fatty acids. Stearate may raise serum triglycerides and decrease high-density lipoprotein (HDL) cholesterol, resulting in no net change in the LDL:HDL ratio. Some data also indicate that stearic acid increases levels of Lp(a), a highly atherogenic variant of LDL, and increases fibrinogen levels, potentially affecting coagulation negatively. Whether stearic acid is prothrombogenic remains unclear, as animal model data may not apply to humans and no intervention trials have yet been completed.

Like red wine and other flavonoid-containing foods, cocoa has been shown to possess antioxidant properties with respect to LDL, similar to those of vitamin E. One cup of hot chocolate containing two tablespoons of cocoa and a 1.5-oz chunk of milk chocolate (41g) contain 146 mg and 105 mg of total phenols, respectively, compared with 210 mg in 140 ml of red wine. Extracted cocoa phenols inhibited LDL oxidation by 75%; researchers concluded that "the pleasant pairing of red wine and dark chocolate could have synergistic advantages beyond their complementary tastes." In a follow-up study, cocoa prolonged the oxidation lag time of LDL in a concentration-dependent manner. Volunteers consumed 35 g of de-lipidated cocoa, and LDL oxidation was measured before and three hours after consumption. LDL oxidation lag time was prolonged significantly (p < 0.005) at two hours. These results support allowing moderate chocolate consumption for patients at risk of atherosclerosis or with coronary heart disease.

The bottom line on chocolate as part of the diet suggests that two to three chocolate bars per week (1.5 oz each), or a daily cup of cocoa with added skim milk, is acceptable. Dark chocolate, which contains less fat, is preferable to sweeter varieties, and cocoa is better still in terms of calories and fat, containing 10% to 22% fat compared with 58% in solid chocolate. Equivalent snacks in caloric terms include 1 oz pretzels with a 12-oz soft drink, or a bag of potato chips with a 12-oz soft drink. Chocolate can also serve as an occasional snack for diabetics and can fit within a Step 1 cholesterol-lowering diet.