Penn State Department of Family and Community Medicine, Penn State College of Medicine, Hershey (Dr. Malone); Torrance Memorial Physician Network, Calif (Dr. Tsai) malm0001@hotmail.com
The authors reported no potential conflict of interest relevant to this article.
Multiple studies have shown that chocolate is associated with a reduction in cardiovascular risk.
Dark chocolate appears to have the greatest benefit, as milk binds to antioxidants in chocolate, making them unavailable. Therefore, milk chocolate is not a good antioxidant source. There is no specific amount of chocolate that is known to be ideal, but an average of one to 2 ounces per day is often used in studies.
Cardiovascular effects . Chocolate does contain saturated fat, but a comparative, double-blind study found that short-term use of cocoa powder lowered plasma low-density lipoprotein (LDL) cholesterol, oxidized LDL, and apo B concentrations, and the plasma high-density lipoprotein (HDL) cholesterol concentration increased, relative to baseline in the low-, middle-, and high- cocoagroups.52 A small randomized crossover trial without clinical outcomes indicated that chocolate may increase HDL cholesterol without increasing weight. 53
A meta-analysis of short-term (2-12 weeks) treatment with dark chocolate/cocoa products showed reductions in LDL and total cholesterol, but no changes in HDL or triglycerides. 54 Another meta-analysis of RCTs, however, showed no short-term effect of cocoa/chocolate on lipid concentrations. 55 A randomized, placebo-controlled double-blind study of 62 patients with diabetes and hypertension showed that high polyphenol chocolateimproved triglyceride levels. 56
Chocolate intake was associated with a lower risk of cognitive decline, with the greatest benefit noted in those who averaged more than one chocolate bar per week.
Multiple studies have shown that chocolate is associated with a reduction in cardiovascular risk. 57-59 A best case scenario analysis using a Markov model to predict the long-term effectiveness and cost effectiveness of daily dark chocolateconsumption in a population with metabolic syndrome at high risk of cardiovasculardisease concluded that daily consumption of dark chocolatecan reduce cardiovascularevents by 85 per 10,000 population treated over 10 years. The study concluded that $42 could be cost effectively spent per person per year on prevention strategies using dark chocolate.59
In addition, a meta-analysis of 7 observational studies showed that high levels of chocolate consumption (any type) were associated with a 29% reduction in stroke compared with the lowest levels of chocolate intake. 57 Results of a similar meta-analysis from Neurology in 2012 also suggested that moderate chocolate consumption (any type) may lower the risk of stroke. 60
That said, 2 systematic reviews specifically relating to the risk of coronary heart disease and chocolate intake were inconclusive. 61-62
Blood pressure (BP) . An RCT published in JAMA indicates that inclusion of small amounts of polyphenol-rich darkchocolateas part of a usual diet efficiently reduced BP and improved the formation of vasodilative nitric oxide. 63 A meta-analysis of 10 RCTs also showed mean BP change in the active cocoa treatment arms across all trials was -4.5 mm Hg (95% confidence interval (CI), -5.9 to -3.2; P<.001) for systolic BP and -2.5 mm Hg (95% CI, -3.9 to -1.2; P<.001) for diastolic BP. 64
A Cochrane Review meta-analysis of 20 studies revealed a statistically significant BP-reducing effect of flavanol-rich cocoa products compared with control in short-term trials of 2 to 18 weeks' duration. 65 Because studies have shown improvement in BP with chocolate intake, investigations into a role of chocolate in the prevention of preeclampsia have been undertaken. In some studies, chocolate intake was associated with reduced odds of preeclampsia and gestational hypertension. 66,67