Sleep and Belly Fat

Sleep part of necessary "triad of healthy behaviors."
NBC Nightly News (3/3, story 8, 2:20, Williams) reported in an installment of its series "Personal Best," the news outlet interviewed Dr. Grace Penn, of the University of Pennsylvania, who said, "There are a couple of research studies that looked at the association between how much people sleep and whether they are more likely to have heart disease and that association is looking like it's real. ... Sleep is part of a triad of healthy behaviors. Eating right and exercise being the other two." NBC (Bazell), added, "Sleep lab studies show how all three parts interact. Sleeplessness leaves people less motivated to exercise. It also releases stress hormones and alters insulin production, making them eat poorly, gain weight and putting them at risk for diabetes and heart disease."
Sleep may affect belly fat accumulation. The Time (3/3, O'Callaghan) "Wellness" blog reported, "Sleeping too much or too little is associated with a higher prevalence of belly fat," researchers found after assessing more than 1,000 black and Hispanic individuals. According to the paper in Sleep, "in participants ages 40 and younger, sleeping fewer than five hours per night or more than eight hours per night was associated with higher concentrations of abdominal fat and increased body mass index during the five-year study period compared with participants who slept six to seven hours per night." There was, however, "no correlation between sleep duration and belly fat among participants over age 40."