What is the general adult protein recommendation in g/kg/day, and how does it change for athletes and older adults?

• A. 0.8 g/kg/day; athletes 1.2–2.0 g/kg/day; older adults 1.0–1.2 g/kg/day
• B. 1.0 g/kg/day; athletes 0.8–1.0; older adults 0.9–1.1
• C. 0.6 g/kg/day; athletes 0.9–1.3; older adults 0.8–1.0
• D. 1.2 g/kg/day; athletes 1.5–2.5; older adults 1.3–1.7

Answer: (A)

The main idea is how protein needs are expressed per body weight and how they rise with training and aging. For most adults, about 0.8 g of protein per kilogram of body weight per day is enough to meet baseline needs. When someone is training regularly, especially for strength or endurance, protein requirements increase to support repair and adaptations, commonly in the range of roughly 1.2 to 2.0 g/kg/day depending on how hard they train. Older adults also benefit from a higher intake to preserve muscle mass and function, typically around 1.0 to 1.2 g/kg/day. This combination—0.8 g/kg/day for general adults, higher for athletes, and slightly higher for older adults—matches the option that lists those ranges. The other choices either set the baseline too low or too high and don’t align with how needs change with activity or age.