Sleep

Does a Lack of Sleep Cause Weight Gain?

Written by Jewels Doskicz, RN, BA | Reviewed by Mandy Armitage, MD

Updated on July 27, 2026

Reviewed by Karen Hovav, MD, FAAP | March 14, 2026

Key takeaways:

Getting enough quality sleep is important for your overall well-being. Lack of sleep can lead to weight gain due to changes in hormones, circadian rhythm, and eating habits.
Research suggests if you sleep too little, or too much, you may increase your risk of obesity and other chronic conditions.
There are steps you can take to improve the quality of your sleep. These include exercising regularly and maintaining a consistent sleep schedule.

Getting a good night’s sleep is one of the best things you can do for yourself — not only for managing your weight but for your overall well-being. There are real dangers linked with getting too little, or too much, sleep.

Finding a happy medium is important for weight management and your overall health. Here, we’ll review how sleep — or a lack of it — can affect your weight.

Does a lack of sleep cause weight gain?

Reviewed by Sarah Gupta, MD | April 10, 2025

If you’re interested in managing your weight, you may want to take a closer look at your sleep patterns. Not sleeping enough may affect your appetite, activity levels, and hormone levels. It can put you at a higher risk of developing obesity and other chronic conditions. Keep in mind that this applies to children as well. Sleep loss in children increases their risk of gaining excess weight.

Here’s what you need to know.

Imbalance of hormones that regulate appetite

The amount and quality of sleep you’re getting may affect your appetite.

What drives a person to eat is complicated. Hunger isn’t just a physiological need. There’s also a desire to eat that comes from:

Cravings
Habits
Boredom
Emotions

Why people “feel” hungry isn’t as simple as it may seem.

Some research suggests that not getting enough quality sleep can cause changes in the levels of hunger hormones ghrelin and leptin. Both of these hormones work to balance the appetite and weight over time, and poor sleep can disrupt how they normally work.

That said, not all research supports this. So the effect of sleep deprivation likely goes beyond hormonal imbalance.

Reduced energy expenditure

When you don’t sleep enough, your body isn’t getting the restoration it needs. This may lead to a next-day sleep “hangover” that can affect your energy levels. Movement and physical activity are also an important part of weight maintenance.

Some research suggests that there’s a bidirectional relationship between sleep and exercise. This means that exercise may help improve sleep. Likewise, a good night’s sleep may help to improve exercise habits. However, researchers are still working to better understand this relationship.

Increased calorie intake

It's possible that poor sleep can make you more likely to engage in eating habits that contribute to weight gain. Research has also uncovered a link between sleep deprivation and higher calorie intake. It can also make you more likely to choose less nutritious options like calorie-rich foods and carbohydrates.

Cortisol levels

You may have heard of cortisol as the “stress hormone.” This hormone increases in response to physical or mental stress, but it’s not good to have high cortisol all the time. One of the effects of elevated cortisol over time is weight gain.

Researchers have looked into the relationship between cortisol and sleep deprivation, but the findings are mixed. This may be due to study design or how cortisol is tested. But the conclusion remains that more research is needed to understand the effects of sleep on cortisol and weight gain.

Circadian misalignment

Sleep deprivation can affect your circadian rhythm, or sleep-wake cycle. This regulates many processes in your body. But over time, changes in sleep and circadian rhythm can affect your body’s metabolism. It’s likely due to a complex interaction of the brain, hormones, and metabolic processes. Research is ongoing.

Can weight affect sleep quality?

Yes, weight can affect how you sleep. And this can be a frustrating, circular problem. A lack of sleep can lead to weight gain, and increased weight can cause sleep issues. That’s because excess weight can contribute to health conditions that affect sleep, including:

Talk to your healthcare team if you’re concerned about the quality of your sleep. They’ll be able to help determine if there’s an underlying condition causing the problem.

Tips for getting a good night’s sleep

The steps for getting quality sleep are well-researched and relatively easy to put into practice. Consider these healthy sleep tips:

Allow yourself enough time to sleep.
Be consistent with your sleep schedule.
Create a comfortable, quiet sleep environment.
Avoid electronics before bed.
Exercise regularly.
Avoid caffeine in the afternoon and evening.
Avoid or minimize alcohol use.
Try to balance your meals throughout the day.

If you’re still having sleep issues despite taking steps to improve your sleep hygiene, talk with your healthcare team. They can help identify any sleep conditions, suggest sleep testing (if needed), and develop a plan so you can get better sleep.

What is ‘good’ sleep, and why is it important?

Most adults need 7 to 9 hours of sleep per night, while teenagers need about 8 to 10. However, experts estimate that more than one-third of people in the U.S. don’t get the right amount of sleep.

A decent night’s sleep isn’t just about how many hours you’re getting. It’s also about the quality. When you’re sleeping, your brain cycles through non-rapid eye movement (non-REM), or quiet sleep, and rapid eye movement (REM), or active sleep stages. In a high-quality night’s sleep, you cycle through all of these sleep stages multiple times.

Getting enough sleep and cycling through the stages of sleep are important for your mental and physical health. Research suggests that sleeping less than 7 hours a night may increase a person’s risk of obesity and other chronic conditions such as Type 2 diabetes and cardiovascular disease.

Can you get too much sleep?

Yes, research suggests that a long sleep duration (9 or more hours a night) is also problematic. It has been linked to both excess weight and Type 2 diabetes. Oversleeping may also be tied to mental health conditions such as depression and anxiety.

If you regularly sleep more than 9 hours and aren’t feeling well-rested, consider talking to a healthcare professional. The right amount of sleep may be different for each person. There are health hazards with undersleeping and oversleeping. So finding your happy medium with sleep is key.

Frequently asked questions

Yes, research suggests that sleep can affect your hemoglobin A1C (HbA1C or A1C) levels. Variability in sleep duration, or not getting the same amount of sleep each night, may have a negative effect on A1C in people with Type 2 diabetes. Researchers have observed a similar trend in people with prediabetes.

There isn’t a simple answer for how much weight you might gain from lack of sleep. Sleep patterns vary by sex, age, and health conditions. And sleep disturbances also affect people differently. The important part is getting enough quality sleep and getting medical advice if you can’t.

The bottom line

Getting a good night’s sleep is an important part of your physical and emotional well-being. Researchers are still working to understand the relationship between sleep and weight, but evidence shows that poor sleep may lead to excess eating, increases in weight, and other chronic health conditions. Consider talking to a healthcare professional if you’re having any sleep issues.

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Written by:

Jewels Doskicz, RN, BA

Jewels Doskicz, RN, is an Arizona-based registered nurse with more than 20 years of hospital-wide clinical nursing experience. She has spent over a decade in medical writing and editing, with a focus on diabetes and autoimmune disease.

Edited by:

Sophie Vergnaud, MD

Sophie Vergnaud, MD, is the Senior Medical Director for GoodRx Health. A pulmonologist and hospitalist, she practiced and taught clinical medicine at hospitals in London for a decade before entering a career in health education and technology.

Reviewed by:

Mandy Armitage, MD

Mandy Armitage, MD, has combined clinical medicine with her passion for education and content development for many years. She is co-executive director at Nonclinical Physicians Network and has served as medical director for the health technology companies HealthLoop (now Get Well) and Doximity.

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References

American Academy of Sleep Medicine. (n.d.). AASM patient guides.

Centers for Disease Control and Prevention. (2024). FastStats: Sleep in adults.

GoodRx Health has strict sourcing policies and relies on primary sources such as medical organizations, governmental agencies, academic institutions, and peer-reviewed scientific journals. Learn more about how we ensure our content is accurate, thorough, and unbiased by reading our editorial guidelines.

Does a Lack of Sleep Cause Weight Gain?

Key takeaways:

Does a lack of sleep cause weight gain?