When we think of weight loss, the first thing that comes to mind is diet and exercise. What most people don’t realise is that sleep plays a major role in weight loss as well. If you haven’t been able to lose weight despite the fact that you’ve been eating right and exercising regularly, it’s time to take a good look at your sleeping habits. Here’s how lack of sleep is affecting your ability to lose weight.
Lack of sleep disrupts the hormones that control appetite, causing you to eat more.
A study published in the Journal of Sleep Research found that even one night of inadequate sleep causes an increase of the hunger hormone ghrelin in your body. According to the researchers, multiple nights of inadequate sleep result in weight gain due to an increased appetite. Another study found that inadequate sleep causes your leptin levels to drop. Leptin is the hormone that tells you when to stop eating.
Inadequate sleep also stresses out your body, which slows down digestion and metabolism.
A study found that even a partial disruption of sleep causes increased levels of the stress hormone cortisol in the body the next day. When your body is stressed, it goes into a primitive flight-or-fight mode that is designed to ensure your survival above all else. In this mode, many of your other bodily functions, including digestion and metabolism, often become much slower, and in cases of extreme stress, they shut down completely. This prevents weight loss because metabolism is the process by which your body breaks down food and uses it for energy, thereby burning calories.
Poor sleep affects insulin resistance as well and can cause weight gain and diabetes.
A study found that sleeping for only five hours a night reduces insulin resistance drastically. Insulin is a hormone secreted by the pancreas that escorts the sugar you eat to your cells, so that it can be used for energy. If your insulin resistance increases, your cells are no longer receptive to the insulin that is being produced and so the sugar you eat does not reach your cells. This causes the sugar to accumulate in your bloodstream, which can lead to weight gain and diabetes.