Dark chocolate and cocoa can help to reduce blood pressure and may improve the serum lipid profile. But can chocolate actually improve heart, diabetes, blood pressure outcomes?
The current meta-analysis finds that higher levels of chocolate consumption are associated with a reduced risk for any cardiovascular disease and of stroke in particular.
Cocoa has been consumed in one form or another for thousands of years, but the modern incarnation of chocolate has been demonized as a possibly addictive food that leads to obesity and poor health outcomes.
However, those who would dismiss chocolate as completely unhealthy should consider some of its basic properties.
Cocoa contains flavonoids, which have antioxidant properties. It also contains high amounts of stearic acid, a saturated fatty acid that does not promote hypercholesterolemia to the same degree as other fats.
Chocolate has proven metabolic effects that suggest a potential for reducing the risk for cardiovascular disease.
In a randomized trial, consumption of solid dark chocolate and liquid cocoa improved endothelial function and blood pressure compared with placebo.
One caveat of this research is that sugar-free cocoa improved these outcomes to a greater extent than regular cocoa. In another trial, consumption of cocoa improved intravascular concentrations of nitric oxide as well as endothelial function in a small cohort of smokers.
Reductions in blood pressure may help to explain why chocolate consumption may improve cardiovascular health.
Large population-based studies have found significant differences in blood pressure based on chocolate consumption, with reductions of 1 to 3 mm Hg in systolic and diastolic blood pressure when comparing groups who consumed the most vs the least chocolate.
In addition, a meta-analysis of 13 randomized studies found that consumption of dark chocolate and cocoa acutely reduced mean systolic and diastolic blood pressure values by -3.2 and -2.0 mm Hg, respectively, compared with placebo.
Chocolate may also help metabolic outcomes, or at least not promote harm. A meta-analysis of short-term trials of dark chocolate and cocoa found that chocolate reduced total cholesterol (mean reduction, and low-density lipoprotein (LDL) cholesterol while having no significant effect on high-density lipoprotein cholesterol or triglycerides.
A significant trend toward a lower risk for incident diabetes among Japanese men who ate more chocolate snacks was also noted, although this trend did not reach statistical significance among women.
These findings are promising but less important if chocolate cannot protect against more severe clinical outcomes, such as myocardial infarction and stroke. There has been research into this subject involving over 100,000 total participants, and the systematic review and meta-analysis by Buitrago-Lopez addresses the collective outcomes of these studies.
- Consumption of dark chocolate and cocoa seems to improve endothelial function and blood pressure.
- The current meta-analysis demonstrates a link between chocolate intake and reductions in cardiovascular disease generally and stroke specifically.
- Chocolate consumption did not seem to be related to the risk for heart failure.
- Chocolate comes in many forms, most of which contain substantial amounts of sugar and fat. Physicians should be careful in advising patients to eat more chocolate as part of a healthy diet.
Dr. Pinna says:
The cacao plant is extremely old. It grows in rain forests where humans dwelled hundreds of thousands of years ago in the tropics of the earth.
Humans have used cacao seeds for thousands of years. When the Spaniards arrived in Mexico they found Montezuma and all the royal family consuming cacao drinks all day long. They were drinking the dark and bitter result of boiling the cacao seeds in water.
All reports say they were extremely healthy. It is unlikely they would drink a bitter liquid if it harmed them. Every study that I have read on cacao, not sweet chocolate, has shown benefit to the participants.