Several factors influence an individual's basal metabolic rate (BMR), including age, gender, muscle mass, and genetics. As people age, BMR tends to decrease due to loss of muscle mass and hormonal changes. Men often have a higher BMR than women because of a greater proportion of lean body mass. Additionally, factors such as activity level and overall health can further impact BMR. Understanding these elements can assist in creating effective dietary and exercise strategies tailored to individual metabolic needs.