It’s common knowledge that lounging around all day will cause some unwanted bulging at your waistline, particularly if you’re no longer 20 years old. Lying around at night, on the other hand, is a completely different story. Getting the right amount of quality sleep each night may play a big role in keeping your weight where you want it. (Maybe that’s why I was in such good shape in college: I slept until 10 AM four days a week!)
All kidding aside, we recently completed an analysis of StayWell health assessment data and found that people who get seven-to-nine hours of quality sleep each night (like the National Sleep Foundation recommends) tend to have a healthier weight than people who sleep either too little or too much. Specifically, for people who reported the recommended hours of sleep, 31% were obese, compared to 42% of people who got too much or too little sleep. That’s a 26% lower likelihood of being obese.
But let’s expand our horizons a bit and look beyond StayWell data. The connection between sleep and weight has been documented, though it’s less clear than I thought it was. Two reviews of the literature (here and here) have documented at least some discrepancies between studies, noting that more research is necessary to understand the nuances of this relationship. It may differ for workers and non-workers, or for different income groups, and it seems age also plays a role.
To complicate matters even more, stress and depression have also been linked to weight gainso questions remain about the directionality of this relationship, and what role sleep plays. Is it that stress leads to lack of sleep, which leads to weight gain? Or does lack of sleep lead to stress, which leads to weight gain? Or some combination of every possible relationship between those three? At this point it’s not clear.The good news is that getting the appropriate amount of quality sleep might help to decrease both depression and stress.
So why would poor sleep habits be associated with being overweight or obese? There are a few possible reasons for this link. First, it makes logical sense: feeling worn out all the time is a definite deterrent to hitting the gym or lacing up your running shoes. Raise your hand if you’ve experienced this.
This logic has led researchers to examine the question, but the matter isn’t quite settled and is an active area of inquiry. A systematic review published in the Fall of 2015 looked at research on how sleep correlates eating and exercising, i.e. things that effect weight.. Without diving too deeply into this review there were several studies in which people who were intentionally sleep deprived were found to eat more, choose larger portion sizes, and report more hunger. However, in this study and this study, researchers found that reduced sleep led to an increase in energy expenditure. You read that right: lack of sleep somehow made people more active.
So, while the relationship between sleep (or lack thereof) and body weight has been demonstrated, the jury is still out on whether poor sleep habits actually cause weight gain. Not to mention the mechanism behind it.
Does that mean you don’t need to worry about your sleep? Heck, no. Getting good sleep is still a good idea. And improving your sleep, or maintaining your good habits, doesn’t have to be complicated. To start, set a schedule and stick to it as much as possible. Getting four hours of sleep one night and 12 the next does not average out to a pair of productive, eight-hour nights. It just leaves your sleep schedule scrambled. You can “make up” for lost sleep or sleep debt, but it takes time and in the interim you’re probably not going to be at your best.
To improve your sleep, the National Sleep Foundation has several recommendations, including:
- Stick to a schedule.
- Have a relaxing routine.
- Exercise daily.
- Design your room for sleep.
- Have a comfortable mattress and pillow(s).
- Avoid alcohol and heavy meals in the evening.
- Wind down.
- Avoid working or watching TV in bed.
Finally, though it’s not specifically on the list, some studies (here and here, among others) have found that smartphone use in the evenings may be negatively impacting your ability to sleep. So stay away from your phone at bed time. Don’t worry. Facebook will still be there in the morning. So will Twitter, LinkedIn, Snapchat, Tinder, Reddit, Tumblr, Instagram…
And for employers? Employers can also play a role in helping their employees get the sleep they need. StayWell recently released the StayWell Sleep program to give employees a clearer picture of what can happen when they don’t get enough shut eye. In addition to a module focused specifically on the links between sleep and weight, the program has modules that focus on napping and on the connection between sleep and overall health.
StayWell Sleep educates individuals with articles, videos and other resources that are all designed to build a better understanding of both the importance of sleep and how to improve sleep habits.
Stay tuned for future blogs on the benefits of sleep and how it affects health, but in the meantime, contact firstname.lastname@example.org to learn more.
In good health,
Stefan Gingerich, MS
Senior Research Analyst