Snoring is a common sleep problem. Hypothyroidism has been linked to increased rates of sleep apnea, and it might contribute to the development of snoring.

Some studies have found that people with low thyroid levels are more prone to developing sleep apnea, a common cause of snoring. Severe hypothyroidism can also lead to weakened respiratory muscles that might contribute to breathing problems that may make you more likely to snore.

Snoring is a common problem that can disrupt your sleep and the people around you. It’s often harmless, but it can be a symptom of an underlying health problem that may need medical treatment, such as obstructive sleep apnea.

Hypothyroidism occurs when thyroid hormone levels are lower than normal. It can cause symptoms like fatigue and weight gain.

Read on to learn more about the connection between snoring and hypothyroidism.

Snoring occurs due to a blockage in your airways while you sleep. Most people snore, at least occasionally. It can have many underlying causes that can be as simple as the anatomy of your throat and mouth.

Hypothyroidism may contribute to the development of snoring for some people. Some research has linked hypothyroidism to increased rates of sleep apnea, which often causes snoring.

Sleep apnea is when you have repetitive pauses in breathing throughout the night. It often causes loud and disruptive snoring. The most common type is obstructive sleep apnea, which is caused by a blockage in your throat.

Severely low thyroid hormone levels can lead to weakness in your respiratory muscles, which may contribute to problems like shortness of breath or breathing difficulty.

Respiratory issues are rarely a major concern in people with hypothyroidism, but they can contribute to the development of sleep apnea, especially in people who remain untreated.

Does hypothyroidism cause sleep apnea?

Researchers have studied the association between hypothyroidism and sleep apnea, but the results have been conflicting. As many as 85% of sleep apnea cases go undiagnosed, which can make finding associations difficult.

In a 2019 study, researchers investigated the association between hypothyroidism and sleep apnea using data from the National Health and Nutrition Examination Survey conducted in the United States from 2007 to 2008.

The researchers found that people with hypothyroidism had a 1.88 times increased risk of having sleep apnea than people with normal thyroid levels.

Higher levels of obesity among people with hypothyroidism may be at least partially responsible for the link. However, in this study, researchers found an increased risk even when accounting for factors like:

  • body weight
  • demographics
  • healthcare access
  • socioeconomic factors
  • alcohol use
  • smoking

Other factors besides obesity that may play a role in the link between hypothyroidism and sleep apnea include:

  • narrowing of the throat caused by deposits of molecules called mucopolysaccharides
  • dysregulation of muscles around your throat
  • dysregulation of respiratory muscles
  • suppression of the respiratory centers in the brain

Some studies have found a relationship between untreated subclinical hypothyroidism and insomnia.

Subclinical hypothyroidism is a mild form where:

In a 2019 study from China, researchers found that, after adjusting for confounding factors, more than 2,000 people with subclinical hypothyroidism had:

  • a 1.12 times higher chance of having poorer sleep quality than people with normal thyroid and TSH levels
  • a 1.16 times elevated risk of having a longer time to fall asleep
  • a 1.15 times higher risk of having a shorter sleep duration

However, other research has been mixed, and some studies haven’t found a significant relationship between insomnia and hypothyroidism.

Hypothyroidism might contribute to insomnia by causing factors that can disrupt your sleep, such as:

  • increased muscle or joint pain
  • poor cold intolerance
  • increased anxiety

Symptoms of hypothyroidism can range from not perceptible to severe. They tend to get worse as your thyroid levels become lower.

Common symptoms can include:

Hyperthyroidism is when your thyroid hormones are above the typical range. It hasn’t specifically been linked to snoring, but it can contribute to other sleep problems. For example, it’s a well-established cause of insomnia.

Because snoring and hyperthyroidism are both relatively common, some people with hyperthyroidism snore for unrelated reasons.

In a 10-year study published in 2023 from China, researchers found an increased risk of nodule growth on the thyroid in people with obstructive sleep apnea and low oxygen levels while sleeping. These growths may play a role in the development of hyperthyroidism.

The findings of this study are contradictory to previous studies that have found a link between low thyroid hormone levels and hypothyroidism.

Hypothyroidism can develop slowly and may cause general symptoms like fatigue. It’s a good idea to see a healthcare professional if you’ve been feeling more tired than usual and there isn’t a clear cause like increased physical activity or poor sleep.

A healthcare professional can measure your thyroid hormones with a blood test and prescribe medications to raise your thyroid hormone levels if needed.

Snoring is a common sleep problem to which hypothyroidism might contribute. It’s a good idea to see a doctor if you suspect you may have hypothyroidism.