7 Health Benefits of Chocolate

In Defense of a Comfort Food

Winning a Nobel Prize may have just gotten easier. Findings published in The New England Journal of Medicine in October 2012 show that countries with more chocolate consumers produce significantly more Nobel laureates, possibly through enhanced cognition.^[1] The study comes on the heels of mounting data showing that chocolate consumption not only improves brain function^[2] but may also proffer a host of other health benefits. The American Chemical Society even devoted an entire 3-hour symposium to the ancient indulgence at their 2012 annual meeting.^[3] Based primarily on Medscape News coverage, and just in time for Valentine's Day, we've reviewed the recent literature purporting health benefits of chocolate.

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Why So Healthy?

Chocolate comes from cocoa beans -- the seeds of the Theobroma cacao tree -- which, along with other plants like tea, are high in flavanols. These abundant phenolic plant compounds have marked antioxidant and anti-inflammatory properties and are thought to be responsible for much of the health benefit ascribed to chocolate consumption. Keep in mind that overly processed chocolate -- most of the candy aisle -- often contains added sugar and saturated fatty acids, which offset cocoa's health benefits. So stick with dark, flavanol-rich varieties.

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Cocoa for Cardiac Health

Ready your best Valentine's pun: recent research suggests that dark, flavanol-rich chocolate may benefit the heart. A 9-year prospective study^[4] of over 30,000 women in the Swedish Mammography Cohort found that those who consumed up to ~1 oz* of high-quality chocolate -- that is, chocolate high in cocoa content -- 1 to 3 times per month had a 26% lower risk of developing heart failure; 1 to 2 servings per week was associated with a 32% risk reduction. No benefits were seen in women consuming 1 or more servings daily; however, more recent work^[5] published in European Heart Journal found that daily dark chocolate consumption over a 4-week period improves endothelial and platelet function in patients with congestive heart failure.^† Chocolate consumption has also been associated with a lower incidence of myocardial infarction and mortality from coronary heart disease.^[4]

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*Most commercial chocolate bars weigh between 1 and 2 oz.

^†Relevant disclosure: This trial was conducted using Nestlé Company chocolate, where one coauthor is an employee.

A Modest Reduction

The vascular benefits of cocoa are reflected in the growing body of evidence linking chocolate consumption with reduced blood pressure. A meta-analysis^[6] published last year in Cochrane Database of Systemic Reviews reported that individuals who consumed about 3.5 oz of dark chocolate every day saw an average blood pressure drop of 2.77/2.20 mm Hg compared with control subjects. Numerous previous studies have linked blood pressure reductions with more reasonable indulgences, even as low as 0.2 oz of chocolate per day.^[7-9] The blood pressure-lowering properties of chocolate are thought to be due to flavanols, which stimulate the production of endothelial nitric oxide, causing vasodilation.

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Fending Off Stroke

Supporting previous research, a 2011 study of the Swedish Mammography Cohort, published in the Journal of the American College of Cardiology, found an inverse relationship between cocoa-rich chocolate consumption in women and stroke: Increasing chocolate consumption by 50 g per week reduced cerebral infarction risk by 12%, hemorrhagic stroke risk by 27%, and total stroke risk by 14%. A more recent study looking at a cohort of over 37,000 Swedish men,^[10] published in Neurology, reported that individuals who eat at least 1.8 oz of chocolate per week have a 17% lower risk for stroke compared with those who eat less than 0.4 oz per week.

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Rethinking Fat

Despite its lipidic reputation, chocolate appears to have a positive influence on cholesterol levels. Most milk and heavily processed chocolate contains added saturated fatty acids, which, along with added sugar, may negate cocoa's health benefits and are likely to raise cholesterol. But dark and unprocessed chocolate, with at least 60%-70% cocoa, is associated with decreased low-density lipoprotein levels and increased high-density lipoprotein levels.^[11-14] Cocoa does contain saturated fat, but it is primarily stearic acid, which is thought to be cholesterol neutral.^[15-17]

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Mixed Results in Mood Disorders

The data on chocolate and depression are conflicting. Although cocoa consumption has been associated with a positive influence on mood,^[18,19] possibly mediated by the dopamine and opioid systems, an extensive review by Parker and colleagues^[19] suggests that the benefits are not sustained, with emotional "comfort" eating actually contributing to depressed mood. Another recent study^[20] found that those with the highest chocolate intake had a greater incidence of depressive symptoms. Researchers acknowledged, however, that in this case, chocolate's mood benefits could be leading to self-medication and that mass-marketed processed chocolate may not have a positive effect. The verdict is still out.

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A Food for Thought

Patients with mild cognitive impairment might benefit from upping their chocolate intake, according to recent findings published in Hypertension.^[2] The Cocoa, Cognition and Aging -- or "CoCoA" -- study found that cognitive function and flexibility as well as verbal fluency scores significantly improved in those who had consumed the highest amount of cocoa flavanols in liquid supplement form, possibly by improving glucose-insulin metabolism.*

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*Relevant disclosure: This trial was funded by Mars Inc.

Really?

A study^[21] from early 2012 published in Archives of Internal Medicine reported, perhaps surprisingly, that frequent chocolate consumption is associated with a lower body mass index (BMI). The authors cited overall diet and chocolate's antioxidant properties as potential contributors to the findings, as well as growing evidence linking chocolate with metabolic benefits (see slides 2 and 6): "[The results are in] accord with other findings suggesting that diet composition, as well as calorie number, may influence BMI. They comport with reported benefits of chocolate to other elements of metabolic syndrome."

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The Bottom Line for Your Patients

With apologies to the milk chocolate inclined, consumption of dark, cocoa- and flavanol-rich chocolate appears to provide significant and varied health benefits. However, all chocolate is caloric -- 2 oz of dark chocolate can contain over 440 calories -- so before your patients get carried away, stress moderate, calorie-conscious consumption and a balanced diet.

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