Which hormone regulates metabolism and growth?

The hormone responsible for regulating metabolism and growth is thyroid hormones. These hormones, primarily thyroxine (T4) and triiodothyronine (T3), are produced by the thyroid gland and have a critical role in controlling the body’s metabolic rate. They influence how quickly the body converts food into energy, impacts heart rate, and affects overall growth and development, especially during childhood and adolescence.

Thyroid hormones also play a significant part in maintaining homeostasis in various physiological processes, including thermoregulation and the metabolic activities of nearly every cell in the body. When levels of thyroid hormones are optimal, they ensure that growth processes occur efficiently, reflecting their integral role in both metabolism and development.

Other hormones mentioned have distinct functions: insulin primarily regulates blood sugar levels and energy storage, adrenaline (or epinephrine) is involved in the body's fight-or-flight response as well as acute energy mobilization, and cortisol is often released in response to stress and helps manage metabolism of fats, proteins, and carbohydrates, but does not directly regulate growth like thyroid hormones do.