How Much Protein Do You Need?
The RDA is 0.8 grams per kilogram of body weight daily (about 0.36g per pound) for average adults - roughly 55g for a 150-lb person. However, athletes, older adults, and those building muscle benefit from more: 1.2-2.0 g/kg. Most Americans already eat enough protein. Spreading intake across meals optimizes muscle protein synthesis better than eating it all at once.
Key Takeaways
- The RDA (0.
- Very high protein intake (above 2.
- Kidney disease patients should limit protein under medical guidance.
Explanation
The RDA (0.8 g/kg) is the minimum to prevent deficiency in sedentary adults, not the optimal amount. Research suggests higher intakes benefit muscle maintenance, satiety, and weight management. Older adults especially benefit from higher protein (1.0-1.2 g/kg) due to reduced muscle synthesis efficiency.
Athletes and those building muscle need more: 1.4-2.0 g/kg for strength athletes, 1.2-1.4 g/kg for endurance athletes. Beyond about 1.6 g/kg, additional protein provides diminishing returns for muscle building. The 'muscle-building window' after exercise is real but larger than once thought - several hours rather than 30 minutes.
Protein sources matter for amino acid profiles. Animal proteins (meat, fish, eggs, dairy) are 'complete,' containing all essential amino acids. Most plant proteins are incomplete but combining sources (rice and beans, for example) provides all essentials. Leucine content is particularly important for muscle synthesis - about 2-3g per meal is optimal.
Things to Know
- Very high protein intake (above 2.0 g/kg) is not harmful for healthy kidneys but provides no additional muscle benefit.
- Kidney disease patients should limit protein under medical guidance.
- Protein needs increase during weight loss to preserve muscle mass.