Lack of Sleep
increases the risk of Obesity
If you are planning to lose weight, in addition to establishing an exercise schedule and a nutritional diet, you must also cultivate good work and rest routine. Insufficient or excessive sleep will affect your weight loss results. According to research conducted by Harvard Medical School, sleeping less than 6 hours a night can increase the risk of obesity and other chronic illnesses.
Unable to sleep? Ghrelin is here!
Lack of sleep not only affects your metabolism but also increases your appetite! The "appetite control centre" is located in the brain's hypothalamus, and consists of the "feeding centre" that controls the feeling of hunger and the "satiety centre" that regulates the feeling of fullness. When the satiety centre is activated, fat tissue will secrete Leptin as a signal to suppress hunger. However, when we are sleep deprived, Ghrelin secretion will spike, causing either an increase in our appetite or the sensation of craving for food shortly after eating. Hence, failing to suppress our desire for food.
Can you burn calories while sleeping?
Every time weight loss is discussed, everyone always associates it with strenuous exercise. However, it turns out that you can burn calories when you are lying down motionless. This is because your body needs a lot of fuel during sleep – Glucose is needed to accomplish many vital tasks! When you fall asleep, your body will begin to work. It not only needs to ensure that various organs can maintain normal function but also required to repair cells and muscles that were damaged during the day. Food also needs to be broken down into fuel to deal with our daily activities. The brain is very active during rapid eye movement (REM) sleep. The heart rate and blood pressure rise using a lot of glucose, making it a period of burning calories.
So, how many calories can be consumed in one night's sleep? This depends on many factors, one of which is the length of sleep. The longer you sleep, the more times you enter the REM stage, the more calories you can burn. Taking a healthy adult weighing 125 pounds as an example, in one hour of sleep, about 38 calories is burned. According to the guidelines of the American National Sleep Foundation, adults aged over 25 need to sleep for an average of 7-8 hours per night. So, one night's sleep consumes 266 calories, which is roughly equivalent to a 200 gram bowl of rice.
Reference:  哈佛醫學院 https://www.health.harvard.edu/topics/sleep  《深短睡眠 — 讓你早晨就強健的根本》福辻銳記著 [3,ﾠ4] 美國國家睡眠基金會 https://www.sleepfoundation.org/articles/how-your-body-uses-calories-while-you-sleep