Sweet news for chocolate fans: A key ingredient in cocoa has been found to benefit people with advanced heart disease and type 2 diabetes.

Researchers at the University of California-San Diego School of Medicine and Veterans Administration San Diego Healthcare System found skeletal muscle improvements in heart and diabetes patients after three months of treatment with epicatechin-enriched cocoa. Epicatechin is a beneficial flavonoid found in dark chocolate.
The results of the small study led investigators to launch a larger clinical trial to assess whether cocoa can boost the ability of heart and diabetes patients to exercise.
The study, published in the journal Clinical and Translational Science, involved five very sick patients with major damage to structures in skeletal muscle cells – known as mitochondria - responsible for energy production. In diabetes and heart patients, these "fuel cells" are dysfunctional and lead to abnormalities in skeletal muscle that leave them short of breath and fatigued.
Patients in the study ate dark chocolate bars and drank a beverage – consuming about 100 milligrams per day of epicatechin. After three months, researchers found significant improvements in the “fuel cells” of the patients.
The results, which confirmed earlier studies showing improvement in skeletal and heart muscle function in animals after treatment with the flavnoid, were promising enough to prompt the larger study, researchers said.
The study was supported in part by the National Institutes of Health, American College of Cardiology and The Hershey Company.