Age-related changes include which of the following?

Age-related changes include which of the following?

• A. Increased total body water
• B. No changes in hydration
• C. Decreased total body water and lower thirst drive
• D. Decreased protein requirements

Answer: (C)

As people age, total body water tends to decrease because lean muscle mass declines and fat mass increases, so there’s less water stored in the body overall. At the same time, the thirst mechanism becomes less responsive, and the kidneys may not concentrate urine as well, which means older adults are more prone to underhydration even when fluids are limited. This combination—lower total body water and a blunted thirst drive—explains why dehydration risk rises with aging. So, describing decreased total body water along with a lower thirst drive captures the typical age-related changes. In contrast, increased total body water isn’t typical, hydration status changes with aging, and protein needs are not decreased—in fact, many older adults may require equal or greater protein to help preserve muscle mass.

As people age, total body water tends to decrease because lean muscle mass declines and fat mass increases, so there’s less water stored in the body overall. At the same time, the thirst mechanism becomes less responsive, and the kidneys may not concentrate urine as well, which means older adults are more prone to underhydration even when fluids are limited. This combination—lower total body water and a blunted thirst drive—explains why dehydration risk rises with aging.

So, describing decreased total body water along with a lower thirst drive captures the typical age-related changes. In contrast, increased total body water isn’t typical, hydration status changes with aging, and protein needs are not decreased—in fact, many older adults may require equal or greater protein to help preserve muscle mass.