Your thyroid quietly controls far more than most people realize, and when it's underactive, the effects touch nearly every part of how you feel day to day. A healthy thyroid supports deep, restorative sleep, stable energy throughout the day, a healthy weight, and strong hair growth. Hypothyroidism disrupts all of it at once, leading to poor sleep, constant fatigue, unexplained weight gain, and noticeable hair thinning. These symptoms often get blamed on stress, aging, or lifestyle, when the real