By Beth Fontenot, MS, RD, LDN
Chocolate may not be health food, but its health benefits continue to mount. A new study from Italy suggests that chocolate may improve walking ability in people with poor blood flow in their legs because of peripheral artery disease (PAD).
In PAD plaque builds up in the arteries that carry blood to the head, organs, arms, and legs. limiting the flow of blood to those parts of the body. People with PAD often experience pain and numbness in their legs, as well as an increased risk of infection.
Chocolate can help; or at least dark chocolate can.
People between the ages of 60 and 78 with PAD were put on a treadmill in the morning to see how far and how long they could walk. Two hours later, on separate days, they were fed 40 grams of either dark chocolate or milk chocolate and asked to walk on the treadmill again.
Those who ate the dark chocolate walked an average of 39 feet farther and 17 seconds longer than they did when they were tested earlier the same morning. Though these are modest improvements, they are potentially relevant for the quality of life of PAD patients, according to Lorenzo Loffredo, M.D., assistant professor at the Sapienza University of Rome, co-author of the study.
Unfortunately for milk chocolate lovers, the sweeter chocolate had no effect on either walking distance or time walked.
The improvements may be the result of polyphenols, compounds found in cocoa, which decrease oxidative stress and increase blood flow to the peripheral arteries. The higher the cocoa content of a chocolate, the more polyphenols it contains. The cocoa content of the dark chocolate used in the study was 85 percent, while the milk chocolate only contained 30 percent cocoa.
After eating chocolate, the levels of nitric oxide rose, and this may be what made the difference. Nitric oxide, a gas produced by cells in the body, has been linked to better blood flow. It may help widen peripheral arteries and ease the symptoms of PAD, particularly pain while walking. Score another one for dark chocolate.
The study lacked a Placebo group, and the participants knew which type of chocolate they were eating, factors that could skew the outcome. A larger study with long-term chocolate consumption is needed to help confirm the results, the researchers said.
Previous research on polyphenols demonstrated improved function of blood vessels, but it's too early to start recommending chocolate for vascular health. For one thing, it's high in calories, sugar, and saturated fat, a fact that can’t be overlooked.
Other foods high in polyphenols with fewer of the diet busters include various spices and dried herbs — such as cloves and peppermint — dark colored berries, flaxseed, chestnuts, hazelnuts, and olives.
It’s possible for chocolate lovers to enjoy their chocolate and reap the potential health benefits. As long as your diet is otherwise healthy, a few ounces of dark chocolate a week is unlikely to have an adverse effect on your health or weight. As with everything, moderation is the key.
The study is published in the Journal of the American Heart Association.
July 3, 2014