Which hormone is secreted by the thyroid and helps regulate metabolism?

Thyroxine, also known as T4, is a key hormone secreted by the thyroid gland that plays a crucial role in the regulation of metabolism. It influences the metabolic rate of nearly every cell in the body by promoting the utilization of glucose and fatty acids, leading to the production of energy. This helps maintain body temperature, supports growth and development, and ensures proper functioning of various organ systems.

Thyroxine achieves this metabolic regulation by increasing the basal metabolic rate (BMR) and aiding in the synthesis of proteins and the metabolism of carbohydrates and fats. Its effects are wide-ranging, influencing energy levels, weight management, and overall metabolic health. This makes T4 essential for maintaining homeostasis in the body.

In contrast, the other hormones provided do not primarily regulate metabolism in the way T4 does. Insulin, for instance, regulates glucose levels but does not have a direct and comprehensive effect on metabolic rate like thyroxine. Cortisol, while it has metabolic effects, primarily manages stress responses rather than overall metabolic regulation. Growth hormone is primarily involved in growth and muscle development instead of direct metabolic regulation. Thus, T4 stands out as the key hormone from the thyroid that specifically targets metabolic processes.