Sleep deprivation is a highly effective interrogation method and is considered by some to be a form of torture. Why? Because, just like food and water, our body needs sleep. Adequate sleep is essential for good health. It supports our immune system, improves memory and brain function, and allows our body to recover and reboot. Another benefit of sleep is that it can help keep off unwanted pounds.
There is an unquestionable link between chronic sleep restriction and obesity (1-4). In both children and adults, those who habitually get less than seven hours of sleep per night tend to be heavier. This link is likely the result of numerous factors, including both behavioral and hormonal changes.
The behavioral changes that result from sleep deprivation are straight forward. People who don’t get enough sleep will be tired the following day and less likely to exercise or be active. They are also awake longer, thus have more time to consume extra calories. Additionally, a lack of sleep tends to promote stress, which in turn encourages unhealthy behaviors, like binge eating and alcohol consumption.
Along with these behavioral changes, hormonal changes also work to encourage weight gain. In a sleep deprived state, our body produces less leptin, a “satiety hormone”, and more ghrelin, a “hunger hormone”. In other words, when we don’t get enough sleep, our body is constantly telling our brain it’s hungry. On top of that, these hormonal changes push us to choose calorie-dense foods, which are often not the healthiest options. It’s like having a tiny person on your shoulder, whispering in your ear all day, “brownies, pizza, doughnuts.”
You may have noticed this feeling of constant hunger after a night of poor sleep. I know I do. When I don’t get my usual eight hours, I turn into a human vacuum the next day. My sleep-deprived self demands all the vegan junk food. Pancakes, hash browns, veggie sausage – get in my belly! Is that a vegan chocolate milkshake? I need that too.
The bottom line is that sleep is important, and not getting enough will result in behavioral and hormonal changes that predispose us for weight gain. Most adults need between 7-9 hours each night. If you have trouble sleeping, or are looking to improve your sleep environment, check out my post Creating the Perfect Sleep Environment.