by: Amanda Dorsey

Reviewed by: Dr. Robert Cooper, M.D., FACE

Review date: 11-13-2008

Underactive thyroid, known as hypothyroidism, is a common problem in America. Affecting about 10 percent of women and 3 percent of men, most people who develop the condition will have it for life.

Hypothyroidism occurs when the thyroid gland doesn’t produce enough of thyroxine (T4) and triiodothyronine (T3) hormones, and can lead to a number of more serious health problems, such as heart disease. Because thyroid hormones are responsible for regulating your metabolism, an underactive thyroid can cause you to put on weight, which may lead to joint pain, obesity, high cholesterol, an enlarged heart or heart failure.

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