Hypothyroidism
Hypothyroidism results from deficient production of thyroid hormone by the thyroid gland. Since the thyroid hormones regulate metabolism in every cell of the body, a deficiency can affect virtually all body functions. Deficiency of thyroid hormones can result from lack of stimulation by the pituitary gland, defective hormone synthesis or impaired cellular conversion of T4 to T3. No matter what the cause, symptoms such as low energy, fatigue, cold hands and feet, muscle pain, depression and cognitive deficits are common.