By Jeremy Appleton, ND, CNS
Healthnotes Newswire (April 27, 2006)—Chocolate lovers worldwide will be interested in some recent research out of Holland: Men who regularly eat chocolate and other cocoa-containing treats have lower blood pressure and may live longer. Although smaller studies have previously shown chocolate’s beneficial effects on blood vessel function, this is the first study to show that eating chocolate and other cocoa-containing foods may improve blood pressure and death rates.
“Ours is the first study that related usual cocoa intake (in other words, from cocoa-containing foods that people eat in daily life) with blood pressure and cardiovascular disease risk,” said Brian Buijsse, lead author of the study. Although this study included only men, Buijsse says that several smaller, previous studies found similar effects of chocolate on blood pressure in both men and women.
Many positive effects of cocoa on human health have been described since antiquity. Eighteenth-century doctors believed cocoa strengthened the heart and relieved a type of chest pain called angina, though that belief has not been studied scientifically. In the 1990s, researchers began discovering that chocolate contained antioxidants with potentially health-promoting effects, and chocolate research has been rapidly increasing ever since.
The present study, published in the Archives of Internal Medicine, examined the relationship between eating or drinking cocoa and incidence of high blood pressure and heart disease in 470 healthy men (ages 65 to 84) over a period of five years. They also examined causes of death during 15 years of follow-up. Compared with men who ate the lowest amounts of cocoa, men who consumed the highest amounts were half as likely to die of cardiovascular disease (or any other cause) during the follow-up period, and on average they also had lower blood pressure.
Before you start your binge, however, be aware that even the highest consumers of chocolate in this study were taking in an average of only about 4 grams (about one-seventh of an ounce) per day.
Although the antioxidants in cocoa could be responsible for the protective effects observed in this study, there may be other reasons for the findings. Men who ate cocoa-containing foods also ate less meat and more nuts and seeds and drank more alcohol and coffee, all of which have potentially protective effects against heart disease when taken in moderation.
The researchers said that the decrease in cardiovascular deaths could not be attributed to lower blood pressure. They point to other effects of the antioxidants in chocolate as plausible causes of protection: improving blood vessel function, lowering cholesterol, improving blood sugar regulation, preventing blood clots, and reducing inflammation.
“We think it is the flavanols in the cocoa that are effective in lowering blood pressure and cardiovascular death risk,” said Buijsse, “but we need more research on this.” Flavanols are a type of antioxidant that occurs naturally in plants.
When asked if this research should change the way we think about eating chocolate and sweets, Buijsse replied, “Chocolate is not only packed with flavanols, but also with calories from sugar and fat.” And excess calories contribute to overweight and obesity, which increase the risk of hypertension, stroke, and diabetes. “This is a bit of the dark side of chocolate,” he added.
Healthnotes Chief Science Editor Alan R. Gaby, MD, who is not connected to the study, recommends moderation. “A very small amount of dark chocolate might be beneficial,” he says, “but people shouldn’t overdo it.”
(Arch Intern Med 2006;166:411–17)
Jeremy Appleton, ND, CNS, is a licensed naturopathic physician, certified nutrition specialist, and published author. Dr. Appleton was the Nutrition Department Chair at the National College of Naturopathic Medicine, has served on the faculty at Bastyr University of Natural Health Sciences, and is a former Healthnotes Senior Science Editor and a founding contributor to Healthnotes Newswire. He has worked extensively in scientific and regulatory affairs in the supplement industry and is now a consultant through his company Praxis Natural Products Consulting and Wellness Services.