Q: How does sleep affect metabolism and weight?
A: In our 24/7 culture, sleep is often sacrificed to get “one more thing” done.
Unfortunately, chronic sleep deprivation, sleep apnea and disruption to circadian rhythms in addition to constant exposure to electronic devices and blue light cause metabolic dysregulation and weight gain. Numerous human studies have shown that sleep-deprived people prefer larger food portions, seek more calories, experience signs of increased food-related impulsivity and experience more fatigue.
According to Michael Breus, PhD, sleep specialist, clinical psychologist and author, sleep affects the metabolic process in four distinct ways.
• First, as you become sleep deprived, your metabolism slows down to try and conserve the resources (food) in it.
• Second, the more sleep deprived you become, the more your internal sympathetic nervous system wants to stay alert and look for food, which raises cortisol in your system.
• Third, with just a small amount of sleep deprivation, we see significant hormonal changes: a 20% increase in ghrelin (the hunger hormone) and a 15% decrease in leptin (the hormone that tells you to stop eating). Lastly, food cravings change with sleep deprivation. When you’re sleep deprived and cortisol is high, your brain wants to calm down and does so by releasing serotonin, which happens when you eat high-fat and high-carb foods.
In addition, lack of sleep increases inflammatory markers and disrupts the gut microbiome. Improving sleep-hygiene habits to get both more and better-quality sleep will help reset any metabolic damage and result in a better weight outcome.