We live in a society that doesn’t value rest. Too much sleep and downtime is considered lazy. Or the other extreme… people sacrifice sleep to exercise or work. When making the choice of opting for less sleep, it’s important to consider the impacts of sleep on weight and well-being. Whether it’s your children’s schedules or your own, the importance of sleep shouldn’t be underestimated.
Many years ago, I went to Dr. Toong – an MD and Chinese medicine doctor. After my check-up, she turned to me and with a warm smile and stated her prescription. She said, “You need vitamin S.” I looked at her, confused and feeling incompetent. I’m a dietitian and had never heard of that vitamin. She smiled and said, “Vitamin S, sleep… the most important medicine there is.”
Sleep impacts not only our behaviour and mood, but also the physiological and hormonal processes in the body.
Mitchell, Rodriguez, Schmitz and Audrain-Mcgovern (2013), who studied adolescents aged 14 to 18, found that the increase of sleep duration from 7.5 to 10 hours a day reduced the proportion of overweight adolescents by 4%. Many studies attempted to explain this phenomenon by looking on how behaviour changed with changes in sleep duration. When feeling sleepy, it is easier to be tempted to choose poor food, such as a snack or a food rich in sugar, to restore energy. Moreover, a lack of sleep has also been found to affect moods, which also have a great impact on one’s food choices. When a person is upset, tired, or sad, they are more likely to choose an unhealthy food item, also known as comfort foods, the sugar in which helps reward centres in the brain create the temporary feeling of happiness. Also, the lack of energy that results from the lack of sleep, results in decreased physical activity and increase in sedentary activities such as watching the TV. It makes sense that when a person gets poor sleep, they do not have energy to exercise, or even cook a healthy meal, all of which can contribute to weight gain and a decrease in health.
As for the physiological aspect of sleep, the activity of two hormones, ghrelin and leptin, that are responsible for metabolism is regulated during sleep. Ghrelin is the appetite encouraging hormone which creates the feeling of hunger, and leptin is the appetite suppressing hormone which creates the feeling of satiety. With a lack of sleep which causes a change in sleep cycles, the regulation of these two hormones is altered, which results in the increase in ghrelin and decrease in leptin, thus creating a continuous appetite and hunger. This means that the person will consume more food throughout the day which will cause weight gain.
Children & Adolescents:
Another hormone to keep in mind is the growth hormone, which is specifically important for children and adolescents and is regulated mainly during sleep. A lack of sleep causes this hormone to be released for a longer period of time rather than in small pulses as with normal sleep; this means that the tissues are exposed to this hormone for longer. Growth hormone decreases insulin sensitivity which is essential for getting glucose into cells; therefore, this prolonged exposure may alter glucose tolerance, which may alter metabolism and increase the risk for weight gain and diabetes. This physiological alteration combined with the behavioural change and a less active lifestyle increase the risk of weight gain, sedentary lifestyle and the possibility of developing chronic diseases.
The bottom line:
Sleep is extremely important, both for children and adults. Even though the exact mechanism through which sleep impacts weight is still being researched, there is a clear link between lack of sleep and weight gain. The National Sleep Foundation released recommendation for the optimal duration of sleep for each age group (see diagram). This recommendation takes into consideration all processes that happen during sleep as well as the average sleep duration needed to prevent major health issues and maintain one’s wellbeing. That being said, the required number of hours of sleep varies for each person and that should be the most important factor to consider. Even though getting enough sleep can be difficult at times, it is important to try, since it is one of the easier habits to alternate in a way to a healthier lifestyle. Many things can be done to ensure longer and more quality sleep, such as:
- Doing a relaxing activity before sleep. Developing a practice of meditation or guided imagery is simpler than it sounds.
- Avoid eating a big meal before sleep
- Keeping the bedroom quiet and dark
- Avoiding sleeping-in on weekends or having long afternoon naps
- Trying to establish a regular sleep schedule and bedtime routine – hot bath, reading, herbal tea…
- Check whether alcohol or caffeine is interfering
- Removing electronics from the bedroom – yes, that includes phones!
Sleep will not only help prevent diseases, maintain a healthy weight and give you energy to be active and do more, it will also make you feel better and happier. And if you can’t fall asleep – don’t stress. My son’s biggest stressor at bed time is that he won’t be able to fall asleep. He’s a night owl and his natural circadian rhythms are probably closer to 12am to 11am! It’s very common for people to not sleep well every single night. Relax your body, read a book and allow sleeplessness to just be.