How Much Protein Do You Need for Muscle Growth?
Quick Take
The general RDA of 0.8 g/kg per day is the minimum to avoid deficiency, not the amount that maximizes muscle. Active adults aiming to build or preserve muscle typically do well with about 1.2–2.0 g/kg per day, with roughly 1.6 g/kg a common practical target. Spread intake across meals for best effect.
Protein is the building material for muscle. When you train with resistance and eat enough protein, your body repairs and adds to muscle tissue. But "enough" is higher than many people assume — the familiar 0.8 g/kg figure is the bare minimum to prevent deficiency in sedentary adults, not the intake that supports training adaptations.
The RDA vs Training Needs
The Recommended Dietary Allowance for protein is 0.8 g per kg of body weight per day. That target was set to meet the needs of about 97% of healthy sedentary adults and is not designed around exercise. Sports-nutrition authorities take a different view for active people.
A joint position stand from the Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine recommends about 1.2 to 2.0 g/kg per day for most exercising individuals. Many individual studies and meta-analyses on muscle protein synthesis land near 1.6 g/kg per day as a practical optimum for building muscle, with higher intakes (up to about 2.0 g/kg) sometimes useful during calorie restriction to preserve lean mass.
From kg to Practical Numbers
To convert your weight, divide pounds by 2.2 to get kilograms. Then multiply by your target:
| Body Weight | ~1.6 g/kg (target) | 2.0 g/kg (upper) |
|---|---|---|
| 140 lb (64 kg) | ~102 g/day | ~128 g/day |
| 180 lb (82 kg) | ~131 g/day | ~164 g/day |
| 220 lb (100 kg) | ~160 g/day | ~200 g/day |
How to Distribute Intake
Muscle protein synthesis responds to each protein-containing meal. Spreading your daily total across three to four meals, with roughly 20–40 g of protein each, tends to support synthesis better than the same amount in one or two large doses. A protein-rich food or supplement shortly after training is convenient but not strictly required if daily totals and distribution are already adequate.
Quality and Sources
"Complete" proteins supply all nine essential amino acids. Animal sources (dairy, eggs, meat, fish) and soy are complete; most plant sources are lower in one or more amino acids but combine well across the day (beans plus rice, for example). For people relying mostly on plants, a slightly higher total intake (toward the upper end of the range) helps compensate for lower digestibility and amino-acid balance.
Do You Need More on a Diet?
During a calorie deficit, protein needs rise because the body is more likely to break down muscle for energy. Pushing toward 1.8–2.0 g/kg while dieting helps preserve lean mass — which is exactly what you want during body recomposition. The recomposition guide covers how this fits with training.
Safety Notes
For healthy people, protein intakes around 2 g/kg per day are generally wellsupported in the literature. Much higher long-term intakes warrant caution in people with existing kidney disease, who should follow their clinician's guidance. Very high protein also displaces other nutrients if it crowds out carbohydrates, fats, and fiber. Use the Macronutrient Calculator to see how protein fits your total calorie budget.