The Link Between Obesity and Sleep

Written by Natalie G., Writer

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We’ve come a long way since the 90s or even early 2000s in terms of better understanding and accepting different body types. Back then, you couldn’t turn on a sitcom without hearing some reference to somebody’s weight. We still have a ways to go in this department, but at least these days we understand that there are many factors that impact overall health.

That said, there are some unique issues that come with obesity and sleep. The two seem to have a cyclical relationship in which obesity can cause sleep issues, and sleep issues can cause weight gain. Our goal here is not to give body image or weight advice but to help you understand the connection between obesity and sleep so that you can get the best sleep possible.

Can Poor Sleep Cause Weight Fluctuations?

Yes, studies show that getting less than seven hours¹ of sleep on a regular basis can lead to gaining weight. There are several reasons for this, the first of which is hormones². When somebody has trouble sleeping through the night or doesn’t get enough total sleep, the body either over or under-produces several hormones, including ghrelin, GHS-R, leptin, insulin, and cortisol.

Ghrelin is the hormone that regulates appetite³. When the body produces too much of it, appetite increases. Conversely, a lack of sleep can lead to a lower production of leptin, which is the hormone that causes you to feel full. This combination means a bigger appetite and less ability to feel full. Additionally, cortisol, which is also referred to as the stress hormone, is widely documented⁴ to cause fat storage, especially around the midsection.

This combination of appetite-regulating hormones plus a lack of energy the next day can lead to an increase in snacking⁵, specifically on foods high in sugar and carbohydrates⁶. Think about it this way: Carbohydrates are the easiest things the body can burn for fuel. If you’re not getting enough sleep and the body needs that energy the next day, it’s going to want carbs and sugar to make up for it.

Furthermore, regular sleep deprivation impacts our cognitive function and mood, which research shows⁷ can make you more likely to eat out and have irregular meal patterns.

We also mentioned above that sleep deprivation will make you more lethargic the next day, which can mean less energy or motivation for exercise.

How Does Being Overweight Affect Sleep?

Just as sleep can affect weight, weight can affect sleep. Excess fat is not just stored on the outside of the body but internally as well, including the airways, throat, and abdomen. This creates less room for the lungs and diaphragm to expand, so often the sleep issues we see with overweight people have to do with breathing.

When we go into REM sleep, our bodies go into a sort of paralysis. This is when the muscles essentially shut down, and it is up to our diaphragm to keep us breathing and maintain a healthy blood oxygen level.

For people who store excess fat near their diaphragm, this important respiratory muscle won’t be able to adequately get oxygen into the body. A low blood oxygen level is called hypoxia⁸, and it triggers a stress response – a flood of hormones designed to increase the heart rate and wake you up so that you can breathe normally again. This is why overweight people tend to wake up abruptly and often throughout the night.

Aside from breathing issues, excess weight can lead to physical pain⁹ and discomfort, particularly lower back pain, leg pain, and musculoskeletal conditions. As you can imagine, this sort of chronic pain can be a major cause of insomnia as well as other sleep issues.

Common Sleep Issues in People Who are Overweight

According to experts, being obese is a risk factor¹⁰ for depression, bipolar disorder, agoraphobia, and panic disorder. This can be caused by multiple factors, just one of which is society’s weight bias and discrimination. One of the outcomes, though, is a negative impact on sleep, as over and over, research has shown mental health disorders like anxiety and depression are a major cause of insomnia¹¹.

Asthma

As we mentioned earlier, being overweight or obese can have a negative impact on the respiratory system. According to the American Lung Association¹², this can lead to the development or worsening of asthma. In fact, their research suggests that people who have a BMI over 30 don’t respond as well to their asthma medications compared to those who have a BMI under 30.

As far as sleep goes, this can mean worse sleep quality, difficulty going to sleep, waking up through the night, and increased daytime sleepiness.

Obstructive Sleep Apnea (OSA)

In the U.S., over 70 percent¹³ of patients with obstructive sleep apnea are also obese. This is because excess fat is also stored internally in the throat and airways. As the name implies, obstructive sleep apnea is caused by an obstruction of the airways, causing blood oxygen levels to drop quickly, resulting in the body jolting awake to resume normal breathing.

Learn more about this sleep disorder in our in-depth <a href=”https://www.sleepadvisor.org/sleep-apnea/

Snoring

With all of the respiratory issues that can come from being overweight, it is not a surprise that overweight people are more likely to snore¹⁴ at night. This can be problematic for couples sharing a bed, but even for solo sleepers, the snoring can be so loud that it can wake up the sleeper.

Learn more about how snoring impacts sleep quality.

Gastroesophageal Reflux Disease (GERD)

Being overweight significantly increases your chances of developing GERD¹⁵, in particular when weight is stored in the abdomen. This extra weight then puts pressure on your stomach and intestines, which can lead to more stomach acid traveling up into the esophagus. The result is heartburn, belching, chest pain, and other uncomfortable symptoms, which can interrupt a good night’s sleep.

Restless Legs Syndrome (RLS)

Overweight or obese adults are more likely to have restless legs syndrome¹⁶ than those who aren’t overweight. Restless legs syndrome – the uncontrollable desire to move your legs, which is often worse in the evening and at night during sleep – is associated with lower dopamine level receptors in the brain. Obesity is also associated with lower dopamine levels in the brain, which scientists suggest may explain the connection¹⁷ between the two.

Explore our picks for the best mattress for restless leg syndrome.

Osteoarthritis

Carrying extra weight has been shown to increase the risk of osteoarthritis and other musculoskeletal issues. This is because extra weight strains the bones, muscles, and joints on a mechanical as well as metabolic level9. Plus, being overweight can increase the body’s overall level of inflammation, which is a key factor in osteoarthritis.

The joint pain and discomfort caused by osteoarthritis can lead to sleep disturbances. In fact, 70 percent¹⁸ of people with osteoarthritis live with some sort of sleep disturbance.

If joint pain disrupts your sleep, browse our best mattresses for arthritis.

How Sleep Deprivation Affects Body Weight

You can blame hormones for this one. Not getting enough bedtime causes a deficiency in the hormone called leptin, which is what makes your body feel full. To make matters worse, it simultaneously increases the production of ghrelin, a hormone that stimulates the appetite.

Not only is your body’s system working against you, but if you’re up for more hours each day, it also makes sense that you’d be hungrier and eat more during waking hours. After all, you can’t eat while you’re asleep!

Poor Diet Choices

Studies show that people tend to make poorer choices when they did not have enough rest. It has to do with the way the brain wires itself when it’s deprived of restorative rest periods. The logic follows that if you’re more likely to exercise poor judgment, your food choices are likely to suffer as well.

Another reason people might binge on cookies and potato chips is due to crankiness and mood swings. Most of us are pretty grumpy when we’re tired, and when we’re not at our best and most positive selves, we might turn to comfort food and fatty carbs to make us feel better.

Less Physical Activity

Being tired during the day because you slept too little the night before means you’re less likely to be active. Tired people tend to watch television when they come home from work, not take a walk or hit the gym.

Low Body Temperature

People who are sleep-deprived have a slightly lower body temperature. When the body temperature drops, you require less energy output to maintain your bodily systems. Less energy expenditure equals lower calorie burn.

Slower Metabolism

When people skip the gym, make poor diet choices, and throw their hormones off balance, the result is a slower metabolism. If you’ve noticed that some people can eat whatever they want and still stay skinny, it’s because their metabolism is higher than average. If you’re not getting enough rest, you slow down your metabolism, making weight loss harder.

Tips to Improve Sleep When Overweight

If you’re currently overweight, there are several things you can do to improve your sleep quality.

Practice good sleep hygiene – Sleep hygiene refers to our daily habits, routines, and the physical space in which we sleep (usually a bedroom). There are many ways to improve your sleep hygiene, but some of the most important include: going to bed at the same time each night (including weekends), stopping screen time 30 minutes to an hour before bedtime, avoiding caffeine or alcohol late in the day, making sure your bedroom is dark, cool, and noise-free, and doing something relaxing before bedtime that helps you wind down.
Improve your diet and nutrition – Improving your diet and nutrition should help you to lose weight, which should help you get better sleep long-term. However, even in the short term, improving diet and nutrition can have an immediate impact on how you sleep as research shows that diets high in saturated fat, sugar, and low in fiber lead to less restorative sleep¹⁹.
Exercise – As with a healthy diet, exercise should help you lose weight and improve your sleep long-term. However, even in the short term, exercise has been shown to improve sleep²⁰ by reducing symptoms of anxiety and depression, physically tiring the body out, and if you exercise outdoors, you get the added benefit of sunlight to regulate your body’s natural circadian rhythm.
Find a great mattress – Often, getting better sleep is as simple as getting a mattress better suited to your body. If you are sleeping on a mattress that isn’t supportive of your weight, it can not only feel uncomfortable, but it can also cause or exacerbate back pain. Instead, a mattress for heavy people could help keep your body in better alignment and improve your sleep quality.

Find out more: 11 Tips to Improve Sleep Quality

Frequently Asked Questions

Can obesity cause sleep apnea and sleep deprivation?

Yes, definitely! Sleep Apnea is often associated with people who are overweight, especially if they carry the extra weight in their neck and torso area. The gravity effect fatigues the muscles and may cause them to “relax” at night, putting them at an angle that cuts off the airways.

Because this is characterized by waking up dozens, if not hundreds, of times per night, it’s no wonder that these conditions are all linked.

Does lack of sleep cause weight gain?

Indirectly, yes. But it’s not like a few all-nighters will automatically pack on the pounds. It’s more a matter of the effect that not sleeping has on your body. First of all, it makes you less likely to have the energy to exercise. Second, it affects hormones that control appetite and blood sugar. And third, being awake for more hours increases your likelihood of taking in more food.

There are a couple of other factors that influence the weight gain as well. Like we mentioned earlier, lack of rest rewires the brain for poor choices. Instead of being logical and making decisions that are best for long-term health benefits, sleep-deprived brains tend to operate in fight-or-flight.

Another side effect is throwing off the body’s circadian rhythm, or internal clock. Shift workers and people who goes to bed at irregular and inconsistent hours demonstrate a 15 to 30 percent higher risk of obesity.

What is sleep apnea obesity hypoventilation syndrome?

This mouthful of a syndrome is also referred to as Pickwickian syndrome. It occurs in people who are extremely overweight, to the point that they’re unable to breathe deeply enough to take in enough oxygen. The result is higher levels of carbon dioxide (CO2) in the blood. It can even cause the patient to stop breathing periodically, hence the inclusion of sleep apnea in the name of this condition.

So how did the name Pickwickian come about? Apparently, it’s named after a Charles Dickens character, supposedly one from his first novel.

What is the best sleep position for obese people?

The most highly recommended position, regardless of weight, is on one’s back, but for those suffering from a condition like apnea, this is the absolute worst position. We recommend that obese people prop themselves up with a wedge pillow to keep their breathing unobstructed and prevent acid reflux.

An adjustable bed frame is another fantastic option. This allows for the benefit of back sleeping at an optimal angle. It also makes getting in and out of bed a lot easier for those who struggle with this task.

Summary

Sleep is one of the most important aspects of our overall physical and mental health and well-being. If we’re not sleeping well, we’re not feeling well.

Unfortunately, being overweight seems to have a direct impact on how well we sleep, and how well we sleep also impacts how much we weigh. Because of this interdependent relationship, it is important to address the issue on both ends: maintaining a healthy weight as well as creating healthy sleep habits.

Getting to and maintaining a healthy weight can be a lifelong process, so in the meanwhile, we recommend improving your sleep while overweight, by implementing a healthy diet, regularly exercising, improving sleep hygiene, and of course, making sure you’re sleeping on the best mattress possible.

Natalie G.

Writer

About Author

Natalie is a content writer for Sleep Advisor with a deep passion for all things health and a fascination with the mysterious activity that is sleep. Outside of writing about sleep, she is a bestselling author, improviser, and creative writing teacher based out of Austin.

Combination Sleeper

References:

Patel, Sanjay R., Malhotra, Atul., et. al. “Association between reduced sleep and weight gain in women”. National Library of Medicine. 2006.
Jetpuri DO, Zaiba., Khan MD, Safia.. “Sleep disorders and obesity: A vicious cycle”. UT Southwestern Medical Center. 2022.
Salamon, Maureen. “Snooze more, eat less? Sleep deprivation may hamper weight control”. Harvard Health Publishing. 2022.
Moyer, A.E., et al. “Stress-induced cortisol response and fat distribution in women”. National Library of Medicine. 1994.
Papatriantafyllou, Evangelia., et al. “Sleep Deprivation: Effects on Weight Loss and Weight Loss Maintenance”. National Library of Medicine. 2022.
Martinez PhD, Suzanna M., et al. “Short Sleep Duration Is Associated With Eating More Carbohydrates and Less Dietary Fat in Mexican American Children”. National Library of Medicine. 2017.
Imaki, Masahide., et al. “An epidemiological study on relationship between the hours of sleep and life style factors in Japanese factory workers”. National Library of Medicine. 2022.
Bhutta, Beenish S., Alghoula, Faysal., Berim, Ilya. “Hypoxia”. National Library of Medicine. 2022.
“Obesity Prevention Source”. Harvard School of Public Health. Webpage accessed April 30, 2024.
Simon, Gregory E., et al. “Association between obesity and psychiatric disorders in the US adult population”. National Library of Medicine. 2006.
Oh, Chang-Myung., et al. “The Effect of Anxiety and Depression on Sleep Quality of Individuals With High Risk for Insomnia: A Population-Based Study”. National Library of Medicine. 2019.
“The Link between Asthma and Weight”. American Lung Association. 2016.
Wolk, Robert., Shamsuzzaman, Abu S.M., Somers, Virend K.. “Obesity, Sleep Apnea, and Hypertension”. AHA Journals. 2003.
“Snoring”. Mayo Clinic. Last modified December 22, 2017.
Chang MD, Paul., Friedenberg MD, Frank. “Obesity and GERD”. National Library of Medicine. 2014.
Lin, Song., et al. “The association between obesity and restless legs syndrome: A systemic review and meta-analysis of observational studies”. National Library of Medicine. 2018.
“Big Belly and Obesity Linked to Increased Risk of Restless Legs Syndrome”. American Academy of Neurology. 2009.
“Osteoarthritis and Sleep”. Arthritis Foundation. Last modified March 15, 2022.
St-Onge PhD, Marie-Pierre., et al. “Fiber and Saturated Fat Are Associated with Sleep Arousals and Slow Wave Sleep”. National Library of Medicine. 2016.
“How Exercise Affects Your Sleep”. Cleveland Clinic. 2020.