It’s not news that walking is good for you. But a recent study found that a sweet treat may make walking a little easier for you if you have painful leg cramping from peripheral artery disease (PAD).
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Prior research showing possible benefits of eating dark chocolate has led to more studies.
Recently, researchers found that eating moderate amounts of dark chocolate prior to exercise might help PAD patients walk longer. Researchers believe polyphenols in the chocolate help to relax narrowed arteries and the better blood flow makes walking easier.
Blood vessel disease and claudication
Claudication is painful cramping that occurs when clogged arteries or atherosclerosis prevent sufficient blood from reaching your muscles, usually in the legs and calves. Patients with peripheral artery disease often have atherosclerosis and symptoms that include claudication. They also have strong risks for coronary artery disease, heart attack and stroke.
Dark chocolate contains polyphenols, a type of antioxidant that some researchers believe helps moderate and prevent clogging of the arteries.
The higher the cocoa content in chocolate, the higher the amount of polyphenol per serving and, in theory, the more healthy properties in the chocolate.
Testing the theory
The new study, conducted at Sapienza University of Rome in Italy, set out to determine if eating dark chocolate would help people with PAD to walk, pain free.
Twenty participants walked as far as they could on a treadmill. Then they ate 40 grams (about the amount in a standard bar) of dark chocolate containing 85 percent cocoa. Two hours later they walked on the treadmill again. The second time, the subjects who had eaten the dark chocolate posted modest gains, walking for 17 seconds longer (almost 39 feet farther) than in their earlier, pre-chocolate walk.
Researchers tried the same experiment with milk chocolate but did not find the same benefits.
In theory, the polyphenol-rich dark chocolate may have helped relax blood vessels, allowing increased blood flow to impacted legs and calves.
[Tweet “Study: #Darkchocolate may help patients with #peripheralarterydisease walk farther with less pain”]Scientists found increased levels of nitric oxide in the participants’ blood after dark chocolate consumption, and also detected reduced biochemical levels of oxidative stress. Both factors might account for increased blood flow and reduced pain from claudication.
Limitations of the study
Vascular medicine specialist Natalie Evans, MD, says the study is interesting, but cautions against reading too much into it. “The study was really small, so I think it is hard to know how significant ultimately this will be,” she says.
The participants all had claudication, which is another limiting factor in the study, she says. “There is a huge population out there with peripheral artery disease, but only about 11 percent of them actually have intermittent claudication, so I think it would be really interesting to find out what impact dark chocolate would have on patients who don’t have this particular condition.”
Enjoy a little dark chocolate – in moderation
The study might whet researchers’ appetite for more involved studies, which will hopefully enlarge the scope and rigor of the investigations.
Meanwhile, if you enjoy eating dark chocolate, continue doing so in moderation. Don’t take any kind of “dark chocolate” antioxidant supplements, though. Recent studies debunk myths about resveratrol in chocolate or red wine helping to reduce risk for cardiovascular disease.
Though the polyphenols studied here differ from resveratrol, the message is the same: Eat healthy foods and a balanced diet and leave the supplements on the store shelf.
Healthy lifestyle still best medicine
Dr. Evans tempers the good news about chocolate with some common-sense advice. “Who wouldn’t want to eat dark chocolate to feel better? But there is a lot more bang for your buck in managing traditional risk factors for PAD, including quitting smoking, avoiding type 2 diabetes and engaging in physical activity,” she says.