How sleep apnea can raise blood sugar and diabetes risk

So much goes on inside your body while you sleep – it’s when you recharge and restore. During those hours, your body fine-tunes your energy levels, balances your hormones and blood sugar and manages your overall metabolism.

When you don’t get enough good-quality sleep, these systems can start to fall out of sync. Over time, that imbalance can make it harder for your body to use energy efficiently and may raise your risk for type 2 diabetes and obesity.¹

How sleep affects hormones

To get quality sleep, your body needs time to cycle through all four sleep stages each night, including deep restorative and REM sleep. During these stages, your body repairs itself, while your mind processes and stores memories – key reasons why quality sleep matters.

When you’re short on rest, your body releases more stress hormones, especially cortisol, which signals your liver to make more glucose for energy. At the same time, levels of growth hormone –which helps maintain your muscles and bones – can drop. Sleep deprivation also interferes with insulin, the hormone that moves glucose from your bloodstream into your cells for fuel.

Over time, these changes can make it harder to maintain a healthy weight or lose excess weight by slowing your body’s ability to turn calories into energy.

Impact on weight, appetite and daily life

At the same time, when you don’t get enough sleep, your body produces more ghrelin, the hormone that makes you feel hungry, and less leptin, the hormone that helps you feel full. As a result, you may eat more and gain weight.

Adding to the challenges, chronic poor sleep can leave you exhausted, making it harder to focus, stay alert or be active. It often causes irritability and low energy, reducing motivation to eat well or exercise – key habits for overall health.

Long-term effects of poor sleep on health

Over time, poor sleep leads your body to produce more glucose (energy) but become less efficient at using it. That throws your blood sugar off balance and can cause it to run high.

Chronically high blood sugar levels can raise your risk for serious health conditions, including high blood pressure, insulin resistance (pre-diabetes), type 2 diabetes, heart disease and depression.

The reverse can also be true. Each of those conditions can make it harder to sleep well, creating a difficult cycle.

For people with a chronic sleep disorder, like obstructive sleep apnea (one of the most common types globally), the health risks and sleep disruptions can become even more serious.

Untreated sleep apnea’s effect on sleep

With obstructive sleep apnea, your breathing stops and starts repeatedly during sleep. These “sleep apnea events” happen when your throat muscles, including your tongue, relax and block your airway. When that happens, you briefly wake up to take a breath, even if you don’t remember it.

These ongoing interruptions make it harder for your body to get enough oxygen. This puts stress on your vital organs, including your heart, lungs and brain. The interruptions disrupt your sleep, too. Even as few as five events per hour can cause poor-quality sleep, affect your blood sugar levels and increase your risk for serious health conditions.

This can create a cycle that can be difficult to break, too. People with untreated sleep apnea often gain weight. This, combined with disrupted blood sugar regulation, increases the risk of developing type 2 diabetes, which is strongly associated with obesity. In turn, carrying extra weight – particularly fat deposits on the chest and around the neck and upper airway – can make it harder to breathe during sleep, further increasing the risk of sleep apnea.

Managing sleep apnea

Many people who have sleep apnea don’t know it. Sometimes, a bed partner or housemate notices symptoms like stopped breathing or loud snoring. Other common signs include:

• Regularly having trouble sleeping

• Feeling exhausted, falling asleep or napping during the day

• Waking up with a dry mouth, headache or sore throat

• Finding it hard to focus or remember things

• Decreased sex drive

• Having mood swings, irritability or quick temper

Fortunately, there are many treatments for sleep apnea. For obstructive sleep apnea, these include oral appliances, continuous positive airway pressure (CPAP) therapy and the implantable Inspire^® therapy. Your doctor can help determine the right option, based on your symptoms, medical history and lifestyle needs.

If you have blood sugar or metabolic concerns, they can help manage those, too.

With appropriate diagnosis and treatment, many people learn to manage their conditions and improve their quality of life. That’s why it’s so important to consult with a healthcare professional if you’re struggling to get enough sleep or experiencing other symptoms.

Sources

1 Sleep Foundation, Sleep & Glucose: How Blood Sugar Can Affect Rest. July 16, 2025.

American Diabetes Association, Obstructive Sleep Apnea as a Cause of Nocturnal Hyperglycemia: A Case Study | Clinical Diabetes. March 30, 2023.

Diabetes UK, Sleep and diabetes. August 23, 2023.

Johns Hopkins Medicine, The Dangers of Uncontrolled Sleep Apnea. Accessed October 15, 2025.

National Heart, Lung and Blood Institute, Sleep Deprivation and Deficiency - How Sleep Affects Your Health. June 15, 2022.

Obesity Medicine Association, Obesity and Sleep Apnea: Understanding the Connection. November 18, 2024.

PMC, Insulin Resistance, Hyperglycemia, and Risk of Developing Obstructive Sleep Apnea in Men and Women in the United States. October 1, 2022.

PMC, The Global Burden of Obstructive Sleep Apnea. April 25, 2025.

Science Direct, Prevalence of prediabetes according to sleep apnea status. February 2025.

Sleep Foundation, How Weight Affects Sleep Apnea. July 15, 2025.