Autoimmune Hypothyroidism: Understanding Hashimoto’s Thyroiditis

Hypothyroidism isn’t always an autoimmune disease. Hashimoto’s thyroiditis, an autoimmune condition where the immune system attacks the thyroid gland, is the most common cause of hypothyroidism in developed countries with adequate iodine intake. However, there are other causes as well.

Common causes of hypothyroidism

Common causes of hypothyroidism include:

• Autoimmune diseases (i.e., Hashimoto’s thyroiditis): Autoimmune diseases like Hashimoto’s thyroiditis involve the immune system attacking the thyroid gland, which eventually leads to hypothyroidism. Graves’ disease, another autoimmune condition, initially causes hyperthyroidism (overactive thyroid), but it may eventually lead to hypothyroidism due to treatment or other factors.

• Thyroiditis (inflammation of the thyroid gland): Inflammation of the thyroid gland, often due to viral infections or autoimmune processes, can lead to temporary or permanent hypothyroidism.

• Certain medications (i.e., lithium): Some medications, like lithium (often used for bipolar disorder), can interfere with thyroid function and cause hypothyroidism.

• Iodine deficiency: A lack of sufficient dietary iodine can impair the thyroid’s ability to produce thyroid hormones, leading to hypothyroidism.
• Thyroid surgery or radiation therapy: Surgical removal of the thyroid gland or radiation treatment for thyroid cancer or other head and neck cancers can result in reduced thyroid function.

• Pituitary gland or hypothalamus disorders: Problems with the pituitary gland or hypothalamus, which are involved in regulating thyroid hormone production, can result in secondary hypothyroidism.

• Congenital thyroid disorders (present at birth): Some babies are born with an underdeveloped or absent thyroid gland, leading to congenital hypothyroidism.

• Aging-related changes in the thyroid gland: As people age, the thyroid gland may function less efficiently, resulting in age-related hypothyroidism.

Hashimoto’s thyroiditis is an autoimmune disease that leads to hypothyroidism. In this condition, the immune system mistakenly attacks the thyroid gland, causing inflammation and damage over time. As a result, the thyroid gland is unable to produce enough thyroid hormones, leading to hypothyroidism.

Hashimoto’s thyroiditis symptoms

Common symptoms of Hashimoto’s thyroiditis may include:

• fatigue and low energy
• dry and pale skin
• hair problems (dry, coarse, brittle, hair loss)
• slowed heart rate
• muscle weakness and cramps
• cold intolerance
• constipation
• weight gain
• mood changes (depression, memory loss)
• swelling in the face and hands
• brittle nails
• hoarse voice or neck pressure from an enlarged thyroid (goiter)

Hashimoto’s thyroiditis is caused by an autoimmune response in which your body’s immune system mistakenly attacks the thyroid gland.

Twin studies show that genetic factors play a significant role, with a 55% chance of both identical twins having the condition, compared to only 3% in nonidentical twins.

Environmental triggers, such as viral infections or exposure to certain substances, may also play a role in triggering Hashimoto’s thyroiditis in genetically susceptible individuals. These triggers may lead to an immune response against the thyroid gland, causing inflammation and damage over time.

The risk factors for autoimmune thyroid disease include:

• family history of thyroid or other autoimmune diseases
• being female (Hashimoto’s thyroiditis is 4–10 times more common in women than men)
• certain genetic factors
• exposure to environmental factors such as low iodine intake and smoking
• age (more common as people get older)
• other autoimmune diseases (having one autoimmune disease, such as lupus, rheumatoid arthritis, or type 1 diabetes, increases the risk of developing others)
• postpartum period for women (research shows that the year following childbirth is a critical time for the onset or worsening of autoimmune diseases, including autoimmune thyroid disorders)

The treatment for Hashimoto’s thyroiditis aims to manage the symptoms and maintain standard thyroid hormone levels. It typically involves:

• Levothyroxine medication: A synthetic form of thyroid hormone, levothyroxine, is prescribed to replace the deficient thyroid hormone and restore standard levels in the body.
• Blood tests: Blood tests are routinely given to check thyroid hormone levels and adjust medication dosage if needed.
• Lifestyle changes: Adopting a healthy lifestyle, including a balanced diet, regular exercise, and stress management, can support your overall well-being.
• Avoiding goitrogenic foods: Some foods can interfere with thyroid function, so it’s advised to limit the consumption of goitrogenic foods like raw cruciferous vegetables (i.e., broccoli, cauliflower) that can affect thyroid hormone production.
• Managing other conditions: If there are other autoimmune diseases or conditions associated with Hashimoto’s thyroiditis, these should be treated and managed.

Hypothyroidism can have multiple causes, with Hashimoto’s thyroiditis being the most common autoimmune factor. Other triggers include iodine deficiency, infections, medications, and more.

If you think you have hypothyroidism, seek a medical evaluation to get an accurate diagnosis and get started on treatment. With the support of healthcare professionals, you’ll be able to effectively manage the condition and improve your quality of life.