Sleep Deprivation and Weight Gain

There are many factors that might lead to gaining weight. Mainly we think of overeating the wrong types of foods and being inactive. Sometimes things in the fitness world don't work the way you think they will. When you strength train you actually are weakening and damaging muscle or if you don't drink water your body may retain it.

Sleep is another. You would think that when you sleep your are not active so your metabolism will slow down. Using this thinking it would seem that if you slept less you would burn more calories throughout the day. Unfortunately, things rarely work this simple.

A recent study in the American Journal of Clinical Nutrition compared energy expenditure over a 24 hour period with normal 8 hours of sleep and sleep deprivation. Researchers found that when participants didn't sleep they reduced their resting energy expenditures by 5% and by 20% after eating food. This means their metabolisms slowed down and there was more food being stored as fat since they didn't need as much for energy.

So it wasn't a huge decrease in energy expenditure, but when you are trying to lose weight this can add up fast. However, this study also looked at hormonal levels after sleeping and not sleeping. After sleep deprivation there was a significant increase in grehlin and cortisol. Here is what each of these hormones is responsible for:

Grehlin- This hormone is found in the stomach and pancreas that stimulates the feeling of hunger.

Cortisol- This hormone is produced by the adrenal gland and released in response to stress and low levels of blood sugar. This hormone is released to increase blood sugar by generating glucose from non carbohydrate sources like lactate, glycerol, and amino acids. Cortisol is also known to suppress the immune system, decrease bone formation, and store fat in the abdominal area.

So we already know that lack of sleep can decrease your energy expenditure during the next day. Now we see these hormones increase meaning you are going to feel hungry so you will likely eat more than normal. Then you will be stressed so your cortisol will make it more likely you get sick, break down muscle tissue for energy, and store those extra calories you just had in your stomach.

Not a great situation to be in. Luckily though it is something you can fix. Make sure you are getting enough sleep each night. General recommendations are for 6-8 hours of sleep but this can be highly individual. If you are noticing your are hungrier than normal, increasing your weight, and getting sick more often maybe try and increase how much you are sleeping.

You Stay Healthy San Diego,

Mike Deibler MS, CSCS
San Diego Premier Training