Hyperthyroidism is a condition in which the thyroid gland releases excessive amounts of thyroid hormone. Symptoms include the following:

    
  • Weight loss
  • Fatigue
  • Fast heart rate
  • Heart palpitations
  • Intolerance to heat
  • Insomnia
  • Anxiety
  • Frequent bowel movements
  • Scant menstruation
  • Bone thinning
  • Hair loss
  • Changes in the appearance of the eye (bulging or staring)
  • Goiter (a visible enlargement of the neck caused by a swollen thyroid gland)
  • The most common form of hyperthyroidism is Grave’s disease. In this condition, the body manufactures antibodies that have the unintended effect of stimulating the thyroid gland. (In another condition, Hashimoto’s thyroiditis , the body produces antibodies that decrease thyroid output.) In addition, benign tumors of the thyroid can secrete excessive thyroid hormone on their own (cancerous tumors seldom do). Viral infection of the thyroid (subacute thyroiditis) causes short-lived hyperthyroidism followed by a more prolonged period of hypothyroidism .

    Medical treatment of hyperthyroidism is highly effective. In most cases of ongoing hyperthyroidism, radioactive iodine is used to destroy thyroid tissue. This approach is both safe and effective, because almost all the iodine in the body ends up in the thyroid, and therefore the radioactive treatment does not damage any other tissues. Other approaches to hyperthyroidism include drugs to block the effects of high thyroid hormone or to slow thyroid hormone production, as well as, in relatively rare cases, surgery.

    Proposed Natural Treatments

    Physician supervision is necessary to determine why the thyroid is overactive in order to design a specific treatment plan. None of the treatments discussed in this section actually get to the root of the problem, nor have they been proven effective. Self-treatment of hyperthyroidism is not recommended.

    Test tube and animal studies suggest that the herb bugleweed may reduce thyroid hormone by decreasing levels of TSH (the hormone that stimulates the thyroid gland) and by impairing thyroid hormone synthesis. 1-5 In addition, bugleweed may block the action of thyroid-stimulating antibodies found in Grave's disease. 2

    The supplement L-carnitine has shown promise for treating a special form of hyperthyroidism that may occur during the treatment of benign goiter. People with benign goiter often take thyroid hormone pills as treatment. Sometimes successful treatment of this condition requires taking slightly more thyroid hormone than the body needs, resulting in symptoms of mild hyperthyroidism. A double-blind, placebo-controlled trial found evidence that use of the supplement L-carnitine could alleviate many of these symptoms. 6 This 6-month study evaluated the effects of L-carnitine in 50 women who were taking thyroid hormone for benign goiter. The results showed that a dose of 2 g or 4 g of carnitine daily protected participants' bones and reduced other symptoms of hyperthyroidism. Carnitine is thought to affect thyroid hormone by blocking its action in cells. 7

    A preliminary trial found some evidence that when the supplement glucomannan is added to standard treatment, normal thyroid hormone levels are restored more rapidly. 14

    For many people, the most problematic symptom of high thyroid is rapid or irregular heartbeat . In cases of temporary high thyroid levels (as in the viral infection form noted above) conventional treatment may involve simply protecting the heart. Germany's Commission E (the herbal regulating body in that country) has authorized use of the herb motherwort as part of an overall treatment plan for an overactive thyroid (hyperthyroidism). 8 Motherwort is said to calm the heart; however, there is no meaningful evidence to indicate that it is effective for the heart-related symptoms of hyperthyroidism (or any other heart-related symptoms).

    Royal jelly has been proposed for use in Grave’s disease, 13 but there is as yet no meaningful evidence that it is effective.

    Herbs and Supplements to Avoid

    According to one study in animals, the herb ashwaghanda may raise thyroid hormone levels. 9 For this reason, it should not be used by people with hyperthyroidism.

    Taking excessive kelp , bladderwrack , or other forms of seaweed can cause hyperthyroidism by overloading the body with iodine. 10-12