By Dr. Asnat Raziel, bariatric surgeon specializing in obesity treatment, metabolic health and healthy longevity; Director of the Multidisciplinary Center for Obesity Treatment, Assia Medical, Assuta Ramat HaChayal, Tel Aviv
Obesity and sleep apnea: two conditions that feed each other
Obesity and sleep apnea often go hand in hand, and each makes the other worse. Excess weight narrows the airway at night, and broken sleep ramps up appetite during the day. The good news: losing weight improves sleep apnea substantially. In this article I explain how to recognize the problem, why it is dangerous, and which treatments work today.
What is obstructive sleep apnea?
In obstructive sleep apnea, the upper airway closes repeatedly during sleep. As a result, blood oxygen levels drop and the brain briefly rouses the body so it can breathe. Most people do not remember these awakenings, but they feel the effects in the morning.
Severity is measured with the AHI (apnea-hypopnea index), the number of pauses and reductions in breathing per hour of sleep. A value of 5 to 14 is considered mild, 15 to 29 moderate, and 30 or more severe. The condition is extremely common: according to a global estimate, about 936 million adults aged 30 to 69 have sleep apnea. Of these, about 425 million have moderate to severe disease.
Obesity and sleep apnea: how excess weight blocks breathing
Fat around the neck, tongue and throat narrows the passage for air. In addition, abdominal fat presses on the diaphragm and reduces lung volume when lying down. So as weight goes up, so does the risk of sleep apnea. A follow-up study from Wisconsin found that a 10% weight gain was associated with a roughly 32% increase in AHI. It also raised the odds of developing moderate to severe sleep apnea sixfold.
The cycle runs in the other direction too. Short, fragmented sleep disrupts the hunger and satiety hormones, making it harder to control eating.
Signs to watch for
The best-known sign is loud snoring, sometimes with pauses in breathing that a partner notices. Other signs include:
- Daytime fatigue and sleepiness, even after a long night
- Morning headaches and a dry mouth
- Getting up at night to urinate
- Difficulty concentrating, irritability and mood changes
- High blood pressure that is hard to control
Diagnosis is made with a sleep study, either in a sleep lab or at home. If you have several of these signs, see your family doctor. Good-quality sleep is also important for brain health and memory.
Obesity and sleep apnea: the risks to the heart and blood sugar
Untreated sleep apnea is not just a snoring problem. The repeated drops in oxygen activate the body’s stress system. Over time, they are linked to high blood pressure, heart rhythm disorders, stroke and insulin resistance. A review of the relationship between the two conditions emphasizes that the combination increases the risk of cardiovascular disease.
That is why treating sleep apnea is part of metabolic treatment. When sleep improves, blood pressure and blood sugar become easier to control. Alongside this, the right lifestyle contributes a great deal to lowering heart risk.
Obesity and sleep apnea: treatment options
Weight loss
Weight loss treats the root of the problem. In the same Wisconsin study, a 10% weight loss was associated with a roughly 26% drop in AHI. In some patients, sleep apnea improves to a mild level or even disappears altogether. Diet, physical activity, medication and surgery can all be combined to achieve this.
CPAP
A CPAP machine delivers air at a constant pressure through a mask, keeping the airway open. It is the standard treatment for moderate to severe sleep apnea, and it improves sleep from the very first night. Many people, however, struggle to stick with it. That is why it is worth choosing a well-fitting mask and getting good guidance.
Medication for obesity and sleep apnea
In recent years, a new tool has been added. In the SURMOUNT-OSA trials, adults with obesity and moderate to severe sleep apnea received tirzepatide, the active ingredient in Mounjaro. After 52 weeks, AHI fell by 25.3 to 29.3 events per hour, compared with about 5 events with placebo. Following these results, the FDA approved the drug in December 2024 for adults with obesity and moderate to severe sleep apnea.
Retatrutide, an investigational drug that has not yet been approved, has also been studied in this area. In the TRIUMPH-1 trial, among 243 participants with sleep apnea, AHI fell by 32.1 to 34.3 events per hour at the higher doses, compared with 9.6 with placebo. You can read about all the drug options on the page medications for obesity and metabolic disease.
Bariatric surgery
In severe obesity, bariatric surgery leads to major weight loss. Afterward, sleep apnea usually improves significantly, but it does not always go away. That is why it is important to repeat the sleep study after weight loss, and not to stop CPAP on your own.
Sleep habits and sleep environment
A few simple steps help everyone: avoid alcohol and sleeping pills before bed, sleep on your side, and keep regular hours. A quiet, dark, well-ventilated bedroom also supports better sleep. I have gathered more ideas in my article on improving sleep naturally.
The bottom line
Obesity and sleep apnea are tightly linked, so the best treatment addresses both together. Losing 10% of body weight already improves nighttime breathing, and new medications add an effective tool alongside CPAP. If you snore, wake up tired or have high blood pressure, it is worth getting a sleep study. You can read more about my approach to treatment on the page about Dr. Asnat Raziel.
The information in this article is general and does not replace personal medical advice.
Questions and answers
Can weight loss cure sleep apnea?
For some patients, yes. A 10% weight loss is associated with a roughly 26% reduction in sleep apnea severity, but this must be confirmed with a repeat sleep study.
Can I stop CPAP once I start medication?
Not on your own. That decision is made only after a repeat sleep study and a conversation with your doctor.
Do obesity and sleep apnea also affect women?
Yes. Sleep apnea is more common in men, but women develop it too, especially after menopause. In women the signs are often less obvious.
Which test diagnoses sleep apnea?
A sleep study, in a sleep lab or at home, measures breathing, blood oxygen and the AHI.
Sources
Tirzepatide for the Treatment of Obstructive Sleep Apnea and Obesity
FDA Approves First Medication for Obstructive Sleep Apnea
Longitudinal study of moderate weight change and sleep-disordered breathing
Retatrutide, a Triple Hormone Receptor Agonist, for Treatment of Obesity
Obstructive Sleep Apnea and Obesity: Implications for Public Health
