Which factors are known to influence Basal Metabolic Rate (BMR)?

Basal Metabolic Rate (BMR) refers to the number of calories the body needs to maintain basic physiological functions at rest, such as breathing, circulation, and cell production. The factors that influence BMR are critical in understanding an individual’s energy expenditure and nutritional needs.

Age is a significant factor because BMR generally decreases with age due to a reduction in muscle mass and changes in hormonal levels. As individuals age, metabolic processes slow down, leading to lower energy requirements.

Gender also plays an important role, as males typically have a higher BMR than females. This difference is largely attributed to males having a higher proportion of lean body mass compared to females, which requires more energy to maintain.

Body composition, specifically the amount of muscle versus fat tissue, directly affects BMR. Muscle tissue is more metabolically active than fat tissue, meaning a person with a greater amount of muscle mass will have a higher BMR.

Hormonal levels can also significantly influence BMR. Thyroid hormones, particularly thyroxine, play a crucial role in metabolic rate. An increase in these hormones can elevate BMR, while a deficiency can lower it.

Thus, the combination of age, gender, body composition, and hormonal levels shapes an individual's BMR, making