Sleep and Obesity; How sleep is influenced by weight and vice versa
Obesity continues to be a major health problem in the United States. According to the National Institute of Diabetes and Digestive and Kidney Diseases, about 68 percent of adults are overweight. Of those, about 35 percent are considered obese.
Several factors play a part in maintaining a healthy weight. What and how much you eat, as well as your activity level are critical factors when it comes to your weight. But that’s not all. It might be surprising to learn that sleep also affects your weight and your weight can affect your sleep.
Sleep and Appetite-Regulating Hormones
Several things influence your appetite including your activity levels and social factors. But the amount of sleep you get also affects certain hormone levels that control appetite. For example, the hormone leptin affects the area of your brain that regulates hunger. Leptin sends a signal to your brain that you’re full. Think of it as a shutoff switch to decrease your appetite. When you don’t get enough sleep, decreased levels of leptin are produced.
A second hormone, ghrelin, acts as a hormone stimulant. The hormone sends a signal to your brain to eat. Higher levels of ghrelin may be produced when you’re sleep deprived.
The bottom line is if you’re not getting the sleep you need, you may have excess levels of ghrelin, which are stimulating your appetite. At the same time, decreased levels of leptin are preventing you from feeling full. It’s easy to see how you would overeat if you’re appetite- regulating hormones are out of balance.
Lack of shut-eye may also decrease glucose tolerance and increase cortisol levels, which may contribute to being overweight. But poor sleep quality also influences your weight in a few other ways. Sleep loss may affect your energy level. For instance, if you’re sleep deprived, it’s harder to push yourself to go to the gym or hit the track.
It may also be more difficult to make healthy eating choices when you’re exhausted. It’s easy to reach for a surgery snack to get an energy boost or go through the drive-thru of a fast-food restaurant for a quick meal.
Obesity and Sleep Disorders
It’s clear; sleep is a key factor in weight management. But weight also affects how well you sleep. For example, obesity is a risk factor for sleep disorders, such as sleep apnea. Sleep apnea develops when the airway becomes obstructed. Someone who is overweight may have extra soft tissue around their neck, which may narrow the airway.
Restless leg syndrome, which can interfere with getting quality sleep, is also linked to obesity. The exact reason how increased weight is associated with restless leg syndrome is not fully understood. But it may be related to increased levels of dopamine.
Getting to a healthy weight may decrease the severity of sleep disorders, such as sleep apnea and restless leg syndrome. In some cases, weight loss may be all that is needed to decrease symptoms.
Can You Get Too Much Sleep?
Lack of sleep is associated with weight gain. So, it might seem that getting a lot of sleep would help with weight management. But not so fast. When it comes to sleep, it’s possible to get too much of a good thing. That’s because routinely oversleeping may also contribute to weight gain.
In a Canadian research study, 276 adults were followed over six years. After adjustments were made for baseline body mass index, age and gender, the participants who were considered short sleepers (five to six hours) were more likely to experience weight gain than average sleepers (seven to eight hours). But those who slept nine to ten hours a night also experienced higher weight gains than average sleepers.
Although individual sleep needs vary, it appears sleeping between seven and eight hours each night is a healthy amount for most adults.
Harvard Medical School. Sleep and Disease Risk. http://healthysleep.med.harvard.edu/healthy/matters/consequences/sleep-and-disease-risk Retrieved February 2017.
National Institute of Diabetes and Digestive and Kidney Disease. Overweight and Obesity Statistics. https://www.niddk.nih.gov/health-information/health-statistics/Pages/overweight-obesity-statistics.aspx Retrieved February 2017.
Chaput, J. Despres, J. Bouchard, C. Tremblay, A., (2008) The Association Between Sleep Duration and Weight Gain in Adults: A Six-year prospective Study from the Quebec Family Study. Sleep. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2279744/ Retrieved February 2017.
Author: MaryAnn DePietro, CRT is a medical writer and licensed respiratory therapist with over a decade of clinical experience.