One meta-analysis, that used data from seven other previously-run studies, showed some good news about chocolate.
These studies didn’t differentiate between the kind of chocolate eaten (dark, milk or white) or the form that the chocolate was in (chocolate bars or other chocolate candy, chocolate in beverages, chocolate in biscuits, cookies and desserts). The frequency of chocolate eating was reported on scales that ranged from “never eating chocolate” to “eats chocolate more than once per day.”
Major benefits for those at risk from heart attack, stroke, and cardiovascular disease
Five of the seven studies showed that the incidence of cardiovascular disease was decreased in people who ate more chocolate. The incidence of stroke was lower in chocolate eaters, and fewer chocolate lovers died from cardiovascular diseases. And (in men) it was noted that increased chocolate consumption correlated with a lower incidence of diabetes. The reductions in the incidences of heart attack, stroke and death from cardiovascular disease were on the order of a 30% decrease. Other studies have shown similar results, that chocolate has benefits for the cardiovascular system. Though a few of those studies showed that dark chocolate (>70% cocoa) was much more effective than other types of chocolate in conferring cardiovascular benefits.
Additional studies have shown that chocolate can help to lessen the risk of heart failure. And chocolate also acts to lower blood pressure. One study done in Sweden, however, showed that overeating chocolate caused its benefits to lessen, eventually becoming zero with eating too much.
How much chocolate is enough?
A definite amount that would confer the maximum benefit for some protection from stroke and other cardiovascular disease isn’t known. But it seems like a serving of about 3/4 to one ounce per day should be adequate.
A downside? Yes, chocolate is high in calories, so increasing intake can cause weight gain. And being overweight can increase the risk of cardiovascular disease. It may increase the risk of developing diabetes. So, if you’re going to add chocolate to your diet, make sure that you adjust your diet accordingly so that you don’t gain weight.
Coffee and tea can provide some benefit too
Several studies have shown that drinking some coffee can help protect against heart disease. But there is a limit to its benefit that is dependent on the amount drunk. Positive effects seem to occur when people drink 1-3 cups (not large mugs) of coffee per day. But negative effects outweigh the positive ones as the number of cups increases above three. In most studies, the coffee used was freshly brewed (not instant) and it was drunk while still fresh.
Tea has been shown to decrease the risk of heart disease. Both black tea and green tea have been studied. Note that these results are for hot, freshly brewed tea, not iced tea. Iced tea, at least in the instant form drunk by most Americans, seems to have almost no effect. With tea, the benefit increases with increasing amounts of tea drunk. That is, people who drank six cups of tea per day had increased benefits over those who drank only one or two cups per day.
Downsides? Caffeine in coffee and tea can increase blood pressure and pulse, and that can be deleterious to cardiovascular well-being. Tea acts as a diuretic and you will urinate more frequently. This can be problematic, not just from a practical standpoint, but can have physiological consequences, as well.
In conclusion, don’t pig out yet
So, should you start eating an ounce of dark chocolate, and drinking three cups of coffee and six cups of tea, a day to decrease your cardiovascular risk?
No. None of these studies looked at STARTING people on coffee, tea and/or chocolate in the hopes that it would prevent cardiovascular disease. The studies looked at people who were ALREADY eating chocolate and drinking tea or coffee. But the studies do suggest that, in these populations, chocolate, limited amounts of coffee, and tea may have a positive effect as reported.