Which statement best describes how energy needs change with age?

Which statement best describes how energy needs change with age?

• A. Energy needs stay the same
• B. Energy needs decline due to decreased lean body mass
• C. Energy needs rise due to increased activity
• D. Energy needs decline, but not related to lean body mass

Answer: (B)

Energy needs generally decrease with age because lean body mass is a major driver of metabolic rate. As people get older, they tend to lose muscle mass (sarcopenia), and muscle tissue burns more calories at rest than fat tissue. When lean mass declines, resting energy expenditure falls, which lowers total energy needs. Activity level often diminishes with age as well, further reducing energy expenditure. So the typical pattern is a decline in energy needs tied to reduced metabolically active tissue; the idea that energy needs rise from increased activity isn’t the norm for aging, and saying the decline isn’t related to lean mass ignores the primary relationship between lean tissue and metabolism.

Energy needs generally decrease with age because lean body mass is a major driver of metabolic rate. As people get older, they tend to lose muscle mass (sarcopenia), and muscle tissue burns more calories at rest than fat tissue. When lean mass declines, resting energy expenditure falls, which lowers total energy needs. Activity level often diminishes with age as well, further reducing energy expenditure. So the typical pattern is a decline in energy needs tied to reduced metabolically active tissue; the idea that energy needs rise from increased activity isn’t the norm for aging, and saying the decline isn’t related to lean mass ignores the primary relationship between lean tissue and metabolism.