Peripheral artery disease (PAD) prevents many people, many of them elderly, from walking easily. Dark chocolate may provide relief, based on a new study.
The disease is characterized by a narrowing of arteries, usually in legs. This is caused by the buildup of plaque in blood vessels, composed of fat, cholesterol and other compounds. The disorder can lead to pain and cramping while walking, and lessen endurance.
A new, small study performed in Italy showed eating dark chocolate could help sufferers become more mobile. Subjects who ate dark chocolate were able to walk for longer periods, and for greater distances, than those who consumed milk chocolate. Testing was performed around two hours after the sweet treat was eaten.
Dark chocolate, made with 85 percent or more cocoa, is rich in polyphenols, while its litter-colored cousin, with around 30 percent cocoa, is not.
Oxidative stress occurs in some patients, leading to stiffness, inflammation and damage to blood vessels. Polyphenols could help reduce that effect, and lead to improved blood flow through extremities.
"Nutrients are key components of health and disease," Lorenzo Loffredo, of Sapienza University in Rome, and lead author of the study, told the press.
Research found 14 men and six women, ages 60 to 78, exhibited improved walking capabilities after eating dark, but not milk, chocolate. Volunteers performed treadmill tests in mornings during the study. Later, participants were provided with around one-and-a-half ounces of chocolate, about the size of a typical candy bar.
On days when dark chocolate was on the menu, subjects showed an average improvement of 11 percent, or 39 feet in distance. They also walked 17 seconds longer, a 15 percent improvement. Milk chocolate had no effect on average performance.
Nitric acid, a chemical known to dilate arteries and improve blood flow, also became more prevalent in subjects who ate polyphenol-rich chocolate. This could have also assisted volunteers with improved mobility.
Polyphenols could also be "of potential relevance for the quality of life of these patients," Loffredo said.
Chocolate contains a large number of calories, making it a dietary concern for many people. Other foods that are also rich in polyphenols include hazelnuts, capers, cloves, dried peppermint and celery seed.
The sample size of this study was extremely small, meaning the results will need to be confirmed by a more extensive experiment in the future. The results of this investigation are promising, but it will be a long time before dark chocolate can be recommended as a treatment for PAD.
Investigation of the role of polyphenols and dark chocolate in PAD was published in the Journal of the American Heart Association.