Calculate the recommended caloric range for a 70-year-old adult given the baseline adult range of 1,800–3,000 kcal/day and the guideline of a 5% reduction per decade after age 50.

• A. 1,800–3,000 kcal/day (no adjustment needed regardless of age according to macronutrient constancy)
• B. 1,440–2,400 kcal/day (assuming 20% reduction for 20 years instead of 5% per decade)
• C. 1,710–2,850 kcal/day (assuming a 5% reduction total for both decades combined rather than per decade)
• D. 1,620–2,700 kcal/day

Answer: (D)