Health benefits of cocoa and chocolate studied

Why is cocoa or chocolate called a mood food? New local and national studies explore why some people use unsweetened dark chocolate as a mood-food and a stimulant to self-medicate for emotional swings. But few studies are discussing chocolate addiction in the mainstream media or in health publications directed to the general consumer.

To avoid sugars, some people are buying unsweetened chocolate or cocoa powder without added sugar or other sweeteners and adding the chocolate or cocoa to their green tea, mint tea, or ginger tea. But why is chocolate used in folkloric medicine for the past 200 years as a remedy for mild depression or emotional swings? Missing from the studies are numerous articles on the addictive nature of chocolate or just how addictive is chocolate? Scientists also are studying brain cannabinoids in chocolate.

Chocolate contains caffeine and other stimulants. But it also reduces blood pressure slightly in hypertensives. Chocolate (in the form of cocoa) helps to reduce insulin resistance, but only when it is unsweetened, as you'd buy in a bar of unsweetened baking chocolate or use unsweetened cocoa powder that wasn't processed with alkali or 'Dutched.' The cocoa has some anti-oxidants.

And why do so many people crave chocolate? Is it the sugar, the taste, or the cocoa that brings customers back for more? Chocolate in its original form in the ancient Americas had been consumed without sugar for centuries as a brew used for healing. Even back then, people were addicted to the hot chocolate drink without added sugar. See the article, Chocolate: Modern Science Investigates an Ancient Medicine.

According to that article, 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. These practices originated among

the Olmec, Maya and Mexica (Aztec).

Early colonial era documents in New England and Virginia included instructions for the medicinal use of cacao as a stimulant. In Europe, the Badianus Codex (1552) noted the use of cacao flowers to treat fatigue, whereas the Florentine Codex (1590) offered a prescription of cacao beans, maize and the herb tlacoxochitl (Calliandra anomala) to alleviate fever and lethargy.

Subsequent 16th to early 20th century manuscripts produced in Europe and New Spain revealed around 100 medicinal uses for cacao/chocolate. Centuries ago the stimulants in chocolate were used to produce changes in the chemistry of the brain, but little is mentioned about chocolate addiction or chocolate cravings.

In the Sacramento-Davis regional area, a recent UC Davis study in the Archives of Internal Medicine published on April 26, 2010 noted in the April 27, 2010 Sacramento Bee article by Anna Tong, "Chocolate linked to depression," also is published in the current issue of the Archives of Internal Medicine, 2010;170(8):699-703, "Chocolate and Depressive Symptoms in a Cross-sectional Analysis." According to the study's abstract, there's quite a lot of folklore about chocolate being the mood food, but hardly any studies on the relationship between mood and chocolate, particularly dark chocolate.

In the study, scientists examined the cross-sectional relationship of chocolate consumption with depressed mood in adult male and females. According to the Sacramento Bee article that looked at the study, chocolate cravings may be your body's message, a way of self-medicating for depression, according to research by a UC Davis Medical Center resident.

If you look at Sacramento/Davis research on chocolate, a scientist at UC Davis gave almost 1,000 men and women two questionnaires about food habits and mood, specifically depression. The study just showed that those that ate the most chocolate were more depressed than those who ate the least chocolate. But what can such a study really say about chocolate's effects on mood?

If you look at European studies done in 2002, just the opposite had been found. One German study found that men in happy or good moods ate more chocolate and depressed or sad men ate less chocolate. In March, 2010, another German study surveyed 19,000 Europeans, according to the Sacramento Bee article, and found those who ate "half a chocolate bar a week had lower blood pressure and a 39 percent lower risk of heart attacks and strokes." On April, 2010, another European study discovered dark chocolate "reduces damage to the blood vessels in patients with liver damage from excessive drinking or disease," according to the Sacramento Bee article.

If you go to the original study published yesterday in the Archives of Internal Medicine, what you can read in the abstract of the study is that the study examined the cross-sectional relationship of chocolate consumption with depressed mood in adult men and women. What does this prove? Either chocolate helps uplift sad people or chocolate depresses people. But there's no evidence in past studies that chocolate has ever caused sadness or depression--just the opposite, probably due to the oxytocin in chocolate that makes the brain think as if it's in love, so to speak.

In the actual cross-sectional analysis done at University of California, Davis, 694 men and 324 women from San Diego, CA were studied. The people were screened to make sure they didn't have diabetes or known coronary artery disease.

The 931 subjects that were not using antidepressants and provided chocolate consumption information were the focus of the analysis. To assess mood, scientists used the Center for Epidemiologic Studies Depression Scale (CES-D).

The scientists used special "cut points" to see whether a positive depression screen resulted. They also used a probable depression score. The chocolate servings each week were provided by the participants in the analysis.

Then the chocolate consumption frequency and rate data were used from the Food Frequency Questionnaires (FFQ). The Food Frequency Questionnaire (FFQ) is the most common dietary assessment tool used in large epidemiologic studies of diet and health. (The chocolate consumption frequency and rate data also were available for 839 subjects.)

The self-administered FFQ booklet asks participants to report the frequency of consumption and portion size of approximately 120 line items over a defined period of time (e.g. the last month; the last three months). Each line item is defined by a series of foods or beverages. Additional questions on food purchasing and preparation methods enable the analysis software to further refine nutrient calculations.

The study compared chocolate consumption for those with lower versus higher "Center for Epidemiologic Studies Depression Scale (CES-D)" scores. Scientists at UC Davis also performed a "test of trend." For more information about tests of trend see, FAQ: A comparison of different tests for trend. The results focused on those screening positive for possible depression, that is people with a specific CES-D score, who had higher chocolate consumption (8.4 servings of chocolate per month) than those not screening positive for depression, who ate 5.4 servings of chocolate per month.

Those with an even still higher score for depression also had higher chocolate consumption, 11.8 servings per month. Those associations applied to men and women. But the findings did not appear to be explained by any increase in fat, carbohydrate, or energy intake. But what can this UC Davis study conclude about chocolate as a mood food for depression?

All the study can say is that higher CES-D depression scores were associated with greater chocolate consumption. So do people eat more and more chocolate when they feel more and more sad or depressed? If you define depression as anger turned inward, does chocolate work as a self-medication to damp down anger or channel it, or help to change a mood of depression to one of joy just by the taste of chocolate?

We know that chocolate is addictive. Does chocolate change the brain due to the ingredients in chocolate? Does it cause the brain to increase its oxytocin levels due to the stimulants in chocolate? Or does the oxytocin increase the feelings of 'love?" Veterinarians give a shot of oxytocin to dogs in labor to help them give birth. It stimulates uterine contractions.

What else does it do for the brain, and why does folklore call chocolate more addictive than heroin? Are there any truths to all the folklore about chocolate being a mood medicine and a stimulant? There is caffeine in chocolate and other stimulants to the brain. But why does it also calm some people? And if you eat chocolate at night, does the caffeine keep you from falling asleep? That depends on your reaction to the caffeine in chocolate. Nobody's making decaf chocolate bars or cocoa powder.

he study could only not that depression scores were associated with greater chocolate consumption. But the study couldn't report in which direction. In other words, is chocolate a mood food you eat to get rid of depression? Or does it cause depression?

So many European studies link chocolate with health benefits in small amounts. The only conclusion you can make is that further study is required. And dark chocolate versus milk chocolate is important to note about a study. In the European studies, dark chocolate was used. Do you think dark chocolate is a mood food? Or do you think it's addictive as self medication for mood enhancement, especially for depressed individuals?

According to the article, "New Evidence That Dark Chocolate Helps Ease Emotional Stress," published online in the Nov. 12, 2009 issue of Medical News Today, the "chocolate cure" for emotional stress is getting new support from a clinical trial published online in the American Chemical Society's Journal of Proteome Research: Gut Microbiota, and Stress-Related Metabolism in Free-Living Subjects. See the study's press release, "Metabolic Effects of Dark Chocolate Consumption on Energy, Gut Microbiota, and Stress-Related Metabolism in Free-Living Subjects."

The American Chemical Society's study found that eating about an ounce and a half of dark chocolate a day for two weeks reduced levels of stress hormones in the bodies of people feeling highly stressed. Interestingly the study found that dark chocolate partially corrected other stress-related biochemical imbalances.

According to the press release, Sunil Kochhar and colleagues looked at growing scientific evidence that antioxidants and various other substances in dark chocolate may reduce risk factors for heart disease and other physical conditions. But consumers want to know what other substances and how does each substance work to balance health and reduce the risk of coronary diseases and emotional risk factors?

The latest study suggested that chocolate may ease emotional stress. But how does dark chocolate reduce stress? What exactly is the evidence?

The most recent study identified reductions in stress hormones and other stress-related biochemical changes in volunteers who rated themselves as highly stressed and ate dark chocolate for two weeks. "The study provides strong evidence that a daily consumption of 40 grams [1.4 ounces] during a period of 2 weeks is sufficient to modify the metabolism of healthy human volunteers," the scientists say.

According to the study's abstract, "Dietary preferences influence basal human metabolism and gut microbiome activity that in turn may have long-term health consequences. The present study reports the metabolic responses of free living subjects to a daily consumption of 40 g of dark chocolate for up to 14 days. A clinical trial was performed on a population of 30 human subjects, who were classified in low and high anxiety traits using validated psychological questionnaires.

"Biological fluids (urine and blood plasma) were collected during 3 test days at the beginning, midtime and at the end of a 2 week study. NMR and MS-based metabonomics were employed to study global changes in metabolism due to the chocolate consumption. Human subjects with higher anxiety trait showed a distinct metabolic profile indicative of a different energy homeostasis (lactate, citrate, succinate, trans-aconitate, urea, proline), hormonal metabolism (adrenaline, DOPA, 3-methoxy-tyrosine) and gut microbial activity (methylamines, p-cresol sulfate, hippurate).

"Dark chocolate reduced the urinary excretion of the stress hormone cortisol and catecholamines and partially normalized stress-related differences in energy metabolism (glycine, citrate, trans-aconitate, proline, β-alanine) and gut microbial activities (hippurate and p-cresol sulfate)." That's what consumers want to know--that the dark chocolate (like in 85 percent cocoa) reduced the stress hormones.

"The study provides strong evidence that a daily consumption of 40 g of dark chocolate during a period of 2 weeks is sufficient to modify the metabolism of free living and healthy human subjects, as per variation of both host and gut microbial metabolism." Check out the American Chemical Society's Journal of Proteome Research web site as there are 45 studies referenced in the abstract.

References

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Grassi, D.; Necozione, S.; Lippi, C.; Croce, G.; Valeri, L.; Pasqualetti, P.; Desideri, G.; Blumberg, J. B.; Ferri, C. Cocoa reduces blood pressure and insulin resistance and improves endothelium-dependent vasodilation in hypertensives. Hypertension 2005, 46 ( 2) 398– 405 [CrossRef], [PubMed], [ChemPort]

Taubert, D.; Roesen, R.; Lehmann, C.; Jung, N.; Schomig, E. Effects of low habitual cocoa intake on blood pressure and bioactive nitric oxide: a randomized controlled trial. JAMA, J. Am. Med. Assoc. 2007, 298 ( 1) 49– 60 [CrossRef], [PubMed], [ChemPort]

Parker, G.; Parker, I.; Brotchie, H. Mood state effects of chocolate. J Affect. Disord. 2006, 92 ( 2−3) 149– 1.59 [CrossRef], [PubMed]

D.Tomaso, E.; Beltramo, M.; Piomelli, D. Brain cannabinoids in chocolate. Nature 1996, 382 ( 6593) 677– 678 [CrossRef], [PubMed], [ChemPort]