Lack of Sleep Makes Us Fatter

Pietari Nurmi
Jul 15 · 3 min read

Correct timing of your meals plays a significant role in your sleep health, but also the amount slept has a high impact on your behavior. Lack of sleep has connections to being overweight, type 2 diabetes, and different metabolic disorders. Why does sleep debt make our bodies softer?

1. Resting makes you burn fat

Many people wishing to lose weight, might think that sleep has nothing to do with burning calories, at to do so you need to be doing something active. As said in previous Lessons: while sleeping, your body consumes a lot of energy from the reservoir. This is as long as you don’t have anything in your stomach. Often, when you sleep less, you tend to eat more in the evenings or eat more during the waking hours, which means that your metabolism has less time to rest.

2. Sleep debt increases your appetite

Have you ever wondered why on some days you might not feel hungry at all when on other days you might feel that you need to snack all the time? In a nutshell, two types of hormones control our appetite. The other one increases when our stomach is empty, as the other one makes us feel satisfied after a proper meal. When these two hormones are balanced, our appetite stays normal. But what has sleep to do with this? Sleep deprivation mixes these hormones. Studies have found that accumulating sleep debt increases appetite and makes us feel less satisfied for a shorter time after a meal. In other words, if you sleep less, you eat more, and often more calorie-packed options as your cravings are trying to substitute for the energy loss from sleep debt. If you are chronically sleep-deprived, overeating accumulates throughout the weeks and increases the risk of being overweight and even obese.

3. Sleep debt makes our weight loss efforts inefficient

Even if you can manage your calorie intake while sleep-deprived, sleep debt makes your efforts less effective. One study has found that with sleep-deprived subjects that were losing weight, most of the weight loss was from the muscle tissue, while the subjects that had no accumulated sleep debt were burning fat.

Additional Reading

Panda, S. (2018). The Circadian Code: Lose Weight, Supercharge Your Energy, and Transform Your Health from Morning to Midnight. Rodale Books.

Sharma, S., & Kavuru, M. (2010). Sleep and metabolism: An overview. International Journal of Endocrinology, 2010.