Even mild or subclinical hyperthyroidism, where TSH levels remain within normal limits but T3 and T4 are elevated, has been associated with an increased risk of osteoporosis. ... or HPT, axis - a ...

Hypothyroidism, an underactive thyroid, affects about 5% of the population, while hyperthyroidism, an overactive thyroid, ... (HPT) axis, a feedback system that maintains hormone balance.