In a study published in the Journal of the International Society of Sports Nutrition, researchers from Kingston University in the UK found that dark chocolate may enhance athletic performance. In a study of several volunteers doing cycle tests, one group that ate 40 grams of dark chocolate showed big improvements in work rate (17 percent increase in time trial) and more efficient use of oxygen (6 percent improvement in VO2 Max) compared to the group that didn’t eat chocolate. “Ingestion of dark chocolate for 14 days reduced the oxygen cost of moderate intensity exercise and may be an effective ergogenic [performance-enhancing] aid for short-duration, moderate intensity exercise,” said the researchers. This effect is attributed to dark chocolate’s ability to raise nitric oxide (NO) levels in the blood, just as beetroot does. But chocolate does it via a different mechanism, augmenting NO production via a molecule unique to it, epicatechin. This substance has been shown in separate studies to be a strong antioxidant, mimicking the beneficial action of insulin and improving heart health.