What is the recommended protein intake as a percent of calories?

• A. 10-15%
• B. 20-25%
• C. 25-30%
• D. 15-20%

Answer: (D)

Protein should account for about 15-20 percent of daily calories. This range supports tissue maintenance and repair, enzyme and immune function, and provides a steady supply of essential amino acids without crowding out carbohydrates and fats needed for overall energy. Since protein provides 4 kcal per gram, on a typical 2000 kcal/day diet this corresponds to roughly 300–400 kcal from protein, or about 75–100 g of protein daily, which lines up with the common recommendation of around 0.8 g/kg body weight for many adults. The lower end (10-15%) can be too low for people who are physically active or aging, while higher ranges (20-25% or 25-30%) are usually unnecessary for most individuals and may reduce intake of carbohydrates that provide quick energy. So 15-20% is the best general guidance.