A lack of sleep causing food cravings and weight gain? As if there weren’t enough distractions in this world to prevent us from attaining that lean physique we desire. Unfortunately, we have to add lack of sleep to that list now too. An article published in Sleep and Breathing followed over 21,000 people for 3 years, and found that sleeping less than 5 hours per night was associated with significantly higher levels of obesity compared with those sleeping 7 hours per night. Sleeping more than 8 hours did not provide any additional benefit. It was also discovered that having a highly variable number of hours of sleep (few hours one night and lots the next) was also highly predictive of weight gain. The reason for weight gain caused by a lack of sleep is, like so many other things, hormonally regulated. When you are not getting enough sleep your levels of gherlin increase (a hormone that increases appetite) and levels of leptin go down (a hormone that decreases appetite). In fact, one study in a group of sleep deprived young men exhibiting this hormone imbalance had abnormally strong cravings for calorie dense foods high in carbohydrates. Another study, found that 4 nights of sleep deprivation in healthy middle aged women increased caloric intake by 20%.
Having sufficient REM sleep (the last stage of the sleep cycle in which we dream that is often cut short when we are not getting enough sleep) is crucial for mental sharpness, recovery from exercise, and overall energy levels.
The take home message here is to consistently aim for 7-8 hours of sleep a night to keep your hunger hormones in check. If however, you are making the time for sleep but still having trouble, try these strategies:
- Keep the room cool (20 C or less): our body temperature must drop before we fall asleep
- Keep the room dark: pitch black is ideal as any light will disrupt melatonin production
- No media or work: try and stay off the phone, TV, computer, and even avoid bright lights 30 min before bed to allow for proper melatonin secretion
- Write out a to-do list for the next day before bed so you are aren't thinking of things throughout the night
- Finally, certain supplements can help - my top choices are: 12 – 15gm of hydrolyzed collagen (contains glycine to promote sleep and enhance mental function the following day), 200 mg of magnesium (muscle relaxant), and possibly melatonin in certain individuals