Protein recommendations cause more confusion than almost any other nutrition topic. Official guidelines are dramatically lower than what sports scientists recommend, and the gap between "enough to prevent deficiency" and "optimal for health and performance" is enormous.
The Official RDA — and Why It's a Floor, Not a Target
The Recommended Dietary Allowance is 0.8g per kg of body weight. For a 70 kg adult, that's 56g/day. This represents the minimum to prevent deficiency in sedentary individuals — not an optimal intake. Most researchers consider this a lower bound, not a goal.
Evidence-Based Recommendations by Goal
A 2018 meta-analysis by Morton et al. found protein above ~1.62 g/kg/day didn't produce additional muscle gains in trained individuals.
Protein Per Meal and Timing
Research suggests muscle protein synthesis is maximised with roughly 0.4g/kg per meal across 3–4 meals. For a 75 kg person, that's ~30g per meal.
The "anabolic window" — the idea you must eat protein immediately post-workout — is largely overstated. Total daily protein matters far more than precise timing.
Plant vs. Animal Protein
Animal proteins (meat, eggs, dairy, fish) are "complete" — all essential amino acids in good proportions. Plant proteins are often lower in specific amino acids, particularly leucine (the primary trigger for muscle protein synthesis).
Vegans should aim for the higher end (1.8–2.2 g/kg) and combine complementary sources — rice + beans, tofu + edamame — to ensure amino acid completeness.
Signs You Need More Protein
- Slow recovery and persistent muscle soreness
- Losing muscle despite regular training
- Persistent hunger (protein is the most satiating macro)
- Brittle nails, hair loss, slow wound healing