12 Aug Early to Bed
Early to bed, early to rise, makes one healthy, wealthy and wise! We’ve heard this adage countless times, whether from friends, family or on television! But have you ever heard that sleeping-in through that early morning alarm to hit the gym before work could actually help you to lose weight?! Well, a team of researchers from the University of South Carolina and Arizona State University were privy to this hypothesis, and set out to put it to the test in their own laboratory. They subjected one group of overweight and/or obese adults to an eight week caloric restriction (CR) diet (the longest intervention among all known similar studies conducted to date) and another group to the same CR diet but restricted their weekly sleep time. The sleep restriction group was made to sleep just one hour less than they would normally would between Monday to Friday, and ad libitum on the weekend. On the weekends the sleep restriction group reported sleeping an additional hour than usual, which resulted in an overall net loss of three hours of sleep over an otherwise standard 7-day week. So, what would you guess would happen in this scenario? How is staying up an hour late every school night going to make any difference to dieting, if you’re going to catch up on the weekend anyway? It turns out that among the group on the calorie-restricted diet who slept as usual, 80% percent of measured weight loss was in body fat. Yet among the group who lost three hours of total sleep per week, 80% percent of their weight loss was not body fat but lean body mass i.e. everything but body fat tissue. What these findings reveal is that loss of adequate sleep on a consistent basis leads to risk of successfully shedding body fat – if that’s your goal. Was this what they meant when they coined: “you snooze you lose?”. We’re going sleep on it!
Source: Sleep, 2018 May 1;41(5). DOI: 10.1093/sleep/zsy027.