Hypothyroidism caused by Hashimoto thyroiditis may contribute to insomnia and affect your sleep cycle in multiple ways. Managing hypothyroidism and practicing good sleep hygiene may reduce sleep disturbances.

Hashimoto thyroiditis is an autoimmune condition that affects the thyroid gland, a butterfly-shaped organ in your neck responsible for producing the hormones thyroxine (T4) and triiodothyronine (T3).

Hashimoto thyroiditis is also the leading cause of hypothyroidism, which is when the thyroid gland doesn’t produce enough thyroid hormones to support your body’s functions (underactive thyroid).

Hypothyroidism and sleep cycles may have a bidirectional relationship. This means that sleep habits can affect thyroid function and an underactive thyroid can affect sleep.

While not everyone with Hashimoto thyroiditis experiences insomnia, sleep disturbances are not unusual if you live with hypothyroidism.

Insomnia often occurs among people with hypothyroidism.

If Hashimoto thyroiditis is causing hypothyroidism, insomnia and other sleep disturbances are possible. But insomnia is not considered a formal symptom or diagnostic criterion of Hashimoto thyroiditis.

Sleep disturbances like insomnia are considered possible secondary effects of the complex relationship between sleep cycles and hypothyroidism.

The duration and quality of your sleep influence the levels of thyroid stimulating hormone (TSH) as well as the production of thyroid hormones. Conversely, TSH and thyroid hormone levels can affect what’s known as your “sleep architecture” or the structure and pattern of your sleep cycles.

According to a review from 2021, hypothyroidism is associated with low sleep quality and sleep architecture, which could explain, in part, the characteristic feelings of fatigue in people with low thyroid hormone production.

The exact link between hypothyroidism and insomnia isn’t clear, however. In a 2024 systematic review, researchers explained that no definitive biological link has been found between insomnia (or sleep deprivation) and hypothyroidism symptoms.

According to the review, the bidirectional relationship between sleep and underactive thyroid function, as well as several other mechanisms, likely contribute to the gradual development of insomnia symptoms in people with hypothyroidism.

For example, other hypothyroidism symptoms, such as joint pain, cold intolerance, or depression, also affect sleep cycles and may manifest with insomnia.

More research is needed to understand the relationship between hypothyroidism and sleep cycles, especially when it relates to Hashimoto thyroiditis.

The use of levothyroxine, a medication staple in the treatment of hypothyroidism, can also contribute to insomnia.

Due to the complex reciprocal relationship between an underactive thyroid function and sleep, the treatment of insomnia in Hashimoto thyroiditis often involves treating hypothyroidism and sleep dysfunction.

Hypothyroidism caused by Hashimoto thyroiditis is typically treated by supplementing your body with synthetic T4 (levothyroxine). A doctor will determine the right dose by considering the results of regular thyroid hormone blood tests as well as factors like age, height, weight, and co-occurring health conditions.

Insomnia treatment can involve sleep medications, and a doctor may recommend cognitive behavioral therapy for insomnia (CBT-I). This is a type of psychotherapy specifically developed to help you restructure thoughts and behaviors that may be contributing to a lack of sleep.

Sleep hygiene is also a component of insomnia treatment. Sleep hygiene refers to implementing specific lifestyle habits that help maximize your chances of enough quality sleep at night.

Sleep hygiene tips may include:

  • keeping your room cool, dark, and quiet
  • waking up and going to sleep on a consistent schedule
  • avoiding alcohol and stimulants like caffeine and nicotine before bed
  • developing a pre-bed relaxation routine
  • improving stress management strategies
  • avoiding naps during the day
  • keeping meals light at night and skipping right before bed

Regulating an underactive thyroid in Hashimoto thyroiditis may require thyroid hormone replacement therapy. Lifestyle changes alone can’t boost hormone production enough to minimize symptoms.

But if you have hypothyroidism as a result of Hashimoto thyroiditis, lifestyle modifications can also support thyroid hormone replacement therapy by promoting the overall health of your thyroid, relieving some symptoms, and lowering the associated inflammation in your body.

Lifestyle changes that may support healthy thyroid hormone levels include:

  • eating a balanced, nutrient-rich diet
  • avoiding products that contain endocrine-disrupting chemicals (EDCs) like phthalates and bisphenol A (BPA)
  • cultivating in-the-moment and long-term stress reduction techniques
  • keeping up with adequate iodine intake (this may not apply to every person with Hashimoto thyroiditis)
  • getting regular exercise
  • staying hydrated
  • limiting substance use
  • stopping smoking, if you smoke
  • maintaining a moderate weight

Only a healthcare professional can provide an accurate diagnosis and recommend the management strategies that suit your individual needs.

Hashimoto thyroiditis is an autoimmune thyroid condition that may lead to hypothyroidism, which could contribute to insomnia and other sleep challenges. While no direct biological link has been established between Hashimoto thyroiditis and insomnia, several mechanisms, including an underactive thyroid, may account for their co-occurrence.

Due to the bidirectional relationship between sleep and underactive thyroid function, treating both Hashimoto thyroiditis-related hypothyroidism and insomnia may help improve the symptoms of both conditions.