Living with obstructive sleep apnea (OSA) can sometimes lead to weight gain. This sleep disorder causes repeated airway collapse during sleep, leading to loud snoring, breathing problems, and frequent waking during the night. Poor sleep, OSA, and weight gain can all make each other worse. In the United States, more than 70 percent of people with OSA also have obesity, and having a high body weight can also make OSA symptoms worse.

Excess weight can contribute to sleep apnea when fat around the neck presses down on the airway, making breathing more difficult, especially when lying down. The good news is that losing even a small amount of weight can help with OSA symptoms. One study found that getting more sleep can also improve metabolism and may help with weight loss.

OSA may cause weight gain on its own in four key ways. Read on to learn how this condition might affect your weight and what you can do about it.

4 Ways Obstructive Sleep Apnea Can Cause Weight Gain

OSA symptoms include loud snoring, gasping for air while asleep, daytime sleepiness, morning headaches, and brain fog. Getting good sleep is an important part of staying healthy and feeling your best. Poor sleep, which is common in sleep apnea, can lead to weight gain over time.

Sleep apnea can cause weight gain by disrupting hormone balance, lowering energy levels, and causing insulin resistance.

1. Hunger Hormones and Sleep Apnea

Hormones (chemical messengers in your body) affect how your body burns calories, stores fat, and controls when you feel hungry or full. Excess weight can change hormone levels, and poor-quality sleep can also cause hormone changes that lead to weight gain.

Waking up often at night with OSA puts stress on your body. Sleep apnea triggers a fight-or-flight response to keep you safe, waking you up when your breathing stops. This stress response process floods your body with hormones, including these related to hunger:

• Leptin, which signals fullness — If your body gets too much leptin, you can become resistant to its effects, making it harder to feel full and easier to overeat. One study showed that people with OSA had nearly 50 percent higher leptin levels than people without this condition.
• Ghrelin, which signals hunger — Poor sleep can raise ghrelin levels, making you feel hungrier and more likely to overeat.

Disrupted sleep can throw off both hormones, which is why OSA can cause more food cravings and ongoing hunger, even after eating.

2. Slower Metabolism and Poor Sleep

When you have OSA, your body also releases hormones that can slow your metabolism and lower your energy levels. Disrupted sleep tells your body to store energy rather than burn it, leading to less energy use at rest and more fat storage.

When OSA wakes you up repeatedly, the release of extra hormones includes GHS-R and insulin, which affect how your body stores energy from food. Too much GHS-R promotes fat storage. High insulin levels can cause insulin resistance, making your body store more sugar as fat. Insulin resistance is linked to increased belly fat and can lead to diabetes.

3. Sleep Deprivation and Tiredness

When you aren’t sleeping well because of sleep apnea (or any other reason), it’s harder to get enough exercise to stay at a healthy weight. Frequent wake-ups from OSA disrupt your sleep cycle and lead to fragmented sleep. This may keep you from getting enough rapid eye movement (REM) sleep, the stage that restores your brain the most.

Sleep deprivation lowers your energy for physical activity. This can cause irritability, trouble with decision-making, and other challenges that make it harder to eat healthfully and get enough exercise.

4. Too Little Oxygen in Blood

With OSA, your airway collapses as you sleep, obstructing your ability to breathe. One of the most dangerous effects is hypoxia — not getting enough oxygen in your blood. A healthy blood oxygen level is 90 percent or above. In people with OSA, blood oxygen levels can drop to 88 percent, which is considered severe hypoxia. In uncontrolled OSA, oxygen levels might dip to 70 percent or lower.

When your oxygen level gets this low, your body feels it’s in danger and releases stress hormones. This can cause inflammation — in addition to the weight-related issues discussed above — which can hurt your health and lead to more weight gain.

Hypoxia is dangerous because low oxygen in your blood means less oxygen in your blood vessels and tissues. This puts stress on your heart and contributes to cardiovascular disease.

Treatment Options for Obstructive Sleep Apnea

Learning about the dangers of sleep apnea can be scary, but it’s important to remember that OSA treatments are well tested and effective.

CPAP and Other Obstructive Sleep Apnea Interventions

Using a continuous positive airway pressure machine (CPAP) while you sleep is a common OSA treatment. Your doctor might also recommend a sleep apnea implant or a bilevel positive airway pressure (BiPAP) machine. Some sleep specialists suggest using certain pillows to help you sleep in a more upright position, reducing the amount of pressure on your windpipe.

Weight Management

Losing weight may help with OSA. Even modest weight loss is linked to better OSA symptoms. One study showed that OSA symptoms improved by 26 percent to 32 percent with just a 10 percent reduction in body weight. For some participants, OSA went away completely.

Talk With Your Doctor

If you haven’t been diagnosed with OSA yet, ask your doctor if a polysomnography (sleep study) would be right for you. This test can be done in a sleep lab or at home.

Talking with your doctor about OSA can help you get effective treatment, feel better, improve your quality of life, and even live longer. You’re not alone — work with a sleep medicine specialist or other healthcare provider to create a personalized OSA treatment plan and help protect your long-term health.

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On MySleepApneaTeam, people share their experiences with sleep apnea, get advice, and find support from others who understand.

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