A 2013 study out of Vanderbilt University Medical Center has shown that insulin activity is controlled by the body’s circadian clock. This means that when we eat could be as important as what we eat for reducing our risk of obesity, diabetes and heart disease. The study, conducted on mice, showed that insulin’s ability to remove glucose from the blood slowed down during a fasting phase in a 24-hour cycle, and that it instead converted glucose into fat. Therefore, in order to ensure the most effective insulin action, says the study co-author Carl Johnson, a professor of biological sciences at Vanderbilt, we should eat during our active phase–6 a.m. to 8 p.m.–and resist drinking any caloric beverage or eating during our inactive phase–8 p.m. to 6 a.m. Johnson, who personally follows this rule, believes that although the study was conducted on mice, the results would be the same if applied to humans. In fact, studies on humans are currently underway.