Hypothyroidism is a condition where the thyroid gland under-produces or stops producing thyroxine or T4. T4 has a major role in regulating metabolism. Such individuals can have several issues of which gaining weight is a mild one. It does not typically cause morbid obesity. This is because most individuals who acquire hypothyroidism in the US seek medical attention for other symptoms before they become excessively obese. It is easily treated with a drug called levothyroxine that easily normalizes metabolism.
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