Hormones are the body’s chemical messengers. They act on various tissues and organs in the body to change their behavior. For example, the hormone prolactin stimulates the production of breastmilk.

Sleep is essential for our physical health, mental clarity, and emotional well-being. But have you ever wondered what really controls your sleep-wake cycle? The answer lies largely in your sleep ...

Stress hormones are chemical messengers that play a role in the body’s physiological and behavioral responses to stress. Examples include catecholamines and cortisol. These hormones help initiate the ...

Susan Pierres, a Miami photojournalist who just turned 60, is confused and angry. Ten years ago, when she was approaching menopause, her doctor started her on hormone-replacement therapy, or HRT. “I ...

Sex hormone binding globulin (SHBG) is a protein in your blood that binds certain hormones. It’s produced in the liver and—in smaller amounts—in the testes. It’s an ancient protein that’s found in all ...