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Hypothyroidism

Learn about hypothyroidism, its causes, symptoms like fatigue and weight gain, and how to manage it with medication and lifestyle changes.

Health
Last reviewed: 7/29/2025

Key Takeaways

  • - **Hypothyroidism** occurs when the thyroid gland doesn't make enough thyroid hormones. - The main symptoms are fatigue, weight gain, and sensitivity to cold. - Most people can manage it well with medication and lifestyle changes.

Hypothyroidism - Underactivity of the thyroid gland, reducing metabolism.

Key Takeaways:

  • Hypothyroidism occurs when the thyroid gland doesn't make enough thyroid hormones.
  • The main symptoms are fatigue, weight gain, and sensitivity to cold.
  • Most people can manage it well with medication and lifestyle changes.

What Is Hypothyroidism?

Hypothyroidism, or an underactive thyroid, occurs when the thyroid gland doesn’t produce enough thyroid hormones, which regulate metabolism. The result is a slower metabolic rate affecting:

  1. Energy levels
  2. Weight management
  3. Body temperature regulation

Symptoms of Hypothyroidism:

  1. Fatigue and sluggishness.
  2. Weight Gain, often unexplained.
  3. Cold Sensitivity, even in mild temperatures.
  4. Hair Thinning or dry hair.
  5. Constipation.
  6. Depression or low mood.
  7. Puffy Face or swelling.

Causes of Hypothyroidism:

  1. Hashimoto’s Disease: An autoimmune disorder attacking the thyroid gland.
  2. Iodine Deficiency: A lack of iodine in the diet.
  3. Thyroid Surgery: Removal or damage to the thyroid gland.
  4. Radiation Therapy: Treatment for cancer or hyperthyroidism.

Diagnosis:

  1. Blood Tests: Measure TSH (thyroid-stimulating hormone) and T4 levels.
  2. Thyroid Function Tests: Confirm underactivity of the gland.

Treatment Options:

  1. Hormone Replacement Therapy: Daily synthetic thyroid hormone (levothyroxine).
  2. Diet Adjustments: Incorporating iodine-rich foods and avoiding goitrogens (e.g., soy, cruciferous vegetables).

Managing Hypothyroidism:

  • Regularly monitor thyroid hormone levels with your doctor.
  • Maintain a balanced diet rich in essential nutrients.
  • Stay active to support metabolism and energy levels.

Related Terms:

  1. TSH (Thyroid-Stimulating Hormone): Regulates thyroid hormone production.
  2. Hashimoto’s Disease: Leading cause of hypothyroidism.
  3. Thyroid Hormones - Include T3 (triiodothyronine) and T4 (thyroxine).