Protein Intake Calculator

For muscle growth, the International Society of Sports Nutrition (ISSN) recommends 0.7–1.0 g per pound (1.6–2.2 g/kg) of body weight per day. A 180 lb adult would target 125–180 g/day spread across 3–5 meals with progressive resistance training.

Probably not. The USDA RDA of 0.8 g/kg is the floor to prevent deficiency in sedentary adults — about 58 g for a 160 lb person. ACSM, ISSN, and most sports dietitians recommend 1.2–2.2 g/kg for adults who exercise regularly: 88–160 g for the same 160 lb person.

The European Society for Clinical Nutrition and Metabolism (ESPEN) PROT-AGE guidelines recommend 1.0–1.2 g/kg/day for healthy adults age 65+, increasing to 1.2–1.6 g/kg during illness, recovery, or active resistance training. For a 150 lb senior, that's 68–82 g daily for prevention, up to 109 g during recovery.

Not in healthy adults. Multiple peer-reviewed meta-analyses (including Devries et al. 2018) show no adverse kidney effects from intakes up to 2.5 g/kg in healthy people. The kidney concern applies to those with pre-existing chronic kidney disease, who should follow nephrologist guidance — not healthy adults pursuing muscle or fat-loss goals.

A standard 4 oz (113 g) cooked boneless skinless chicken breast contains about 30–35 g of protein. Other common sources: 4 oz salmon ≈ 25 g, 1 cup cooked lentils ≈ 18 g, 1 cup Greek yogurt (plain) ≈ 17 g, 1 large egg ≈ 6 g, 1 scoop whey ≈ 24 g, 1 oz almonds ≈ 6 g.

Less critical than total daily intake. The "anabolic window" concept (must eat protein within 30 minutes of training) was overstated — the ISSN consensus is that protein intake within several hours of training is fine. Spreading 25–40 g across 3–5 meals through the day matters more for muscle protein synthesis.

Plant proteins work but generally require higher total grams to match animal-source results due to lower leucine content and digestibility. ISSN suggests vegan athletes target the upper end of the recommended range and combine sources (rice + beans, hummus + pita) to improve the amino acid profile. Soy, pea, and quinoa are the closest plant options to "complete."

Higher than maintenance. Helms et al. and the ISSN recommend 1.6–2.4 g/kg during caloric restriction to preserve lean mass. For a 200 lb adult cutting, that's 145–218 g/day. Pair with resistance training to keep muscle while losing fat, and limit deficit to 500 kcal/day for sustainable progress.