Which group generally requires fewer calories as they age?

The correct choice highlights that older adults generally require fewer calories as they age. This reduction in caloric needs can be attributed to several physiological changes that occur as individuals grow older.

As people age, their basal metabolic rate (BMR) tends to decrease. BMR is the rate at which the body uses energy at rest to maintain basic bodily functions such as breathing, circulation, and cell production. Factors contributing to this decline include loss of muscle mass, which typically occurs with aging. Muscle tissue is more metabolically active than fat tissue, so a decrease in muscle mass leads to a lower caloric requirement.

Additionally, older adults often experience changes in physical activity levels, with many becoming less active due to factors such as mobility issues or other health concerns. This decrease in physical activity further contributes to lower caloric needs.

In contrast, teenagers and young adults generally require more calories to support their growth, development, and higher levels of physical activity. Active individuals may also have higher caloric needs based on their energy expenditure during exercise and daily activities.

In summary, the correct answer reflects the general trend of decreased caloric requirements in older adults due to physiological changes and often decreased levels of physical activity. As part of the Exercise is Medicine initiative,