If you've considered buying over-the-counter bovine or herbal thyroid supplements, you might wonder how they differ from the synthetic thyroid hormones prescribed by physicians. Like synthetic thyroid therapy, bovine supplements replace hormones. Herbal supplements may stimulate the thyroid gland to produce more hormone. Always talk to your physician before using any type of supplement to be sure you're targeting the real cause and to avoid potential side effects.
The thyroid is a butterfly-shaped gland in the front of your neck below the Adam's apple. It produces two thyroid hormones called thyroxine, or T4, and triiodothyronine, or T3. These hormones regulate metabolism and affect virtually every system in your body, including normal growth, heart and nervous system functioning, muscle strength, the skin and levels of cholesterol. When the thyroid doesn't produce enough hormone, it's called hypothyroidism. The only way to treat hypothyroidism is by curing the underlying medical condition or by replacing thyroid hormones.
Bovine Thyroid Supplements
Bovine thyroid supplements, also called dessicated thyroid or glandular extract, are made from dried and powdered thyroid glands of cattle. Bovine thyroid extract is a natural substance that's available over the counter and as a prescription medication. Prescription medications are standardized to provide a specific amount of thyroid hormone. Over-the-counter supplements are not regulated. Product labels report how much thyroid tissue is in each tablet, but that does not tell you how much actual hormone is present, or whether it contains T3, T4, or both. Before you take bovine thyroid supplements, talk to your doctor to be sure you're getting what you need.
Herbal Thyroid Supplements
Herbal remedies can't replace thyroid hormones, but some supplements claim that the herb guggul, also called guggulu or Commiphora mukul, stimulates the thyroid to produce more hormones. Research published in the January 2005 issue of "Phytotherapy Research" states that guggulu raised levels of thyroid hormones in laboratory mice. However, there isn't enough information available to determine its safety or effectiveness in humans. Some herbal supplements contain iodine, often in the form of seaweeds, such as bladderwrack or kelp. While the thyroid needs iodine to produce hormones, lack of iodine is seldom the cause of hypothyroidism. Consult your physician before taking iodine supplements because consuming too much can create a thyroid problem.
If your iodine levels are not low, taking supplements could create iodine toxicity. If you take other supplements, herbs or medications, be aware that some might interact with thyroid hormones. Avoid bugleweed and lemon balm because they can interfere with the action of thyroid hormones. Iron might impair the thyroid's ability to make hormones, and soy products limit the absorption of thyroid extract. Some medications used to lower cholesterol, or to treat blood clots, heart disease, asthma or chronic obstructive pulmonary disease can interact with dessicated thyroid. Talk to your physician or seek medical attention if you experience side effects, such as heart palpitations or arrhythmia, chest pain, headache, diarrhea, vomiting, fever or heat intolerance.