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Protein intake
Strong evidenceStrong evidenceMuscleStrength
Evidence
Settled
Target
1.6–2.2 g/kg/day
Applies to
Anyone lifting
Source matters?
No — total counts
Does it work?
- -Yes. Eating enough protein is one of the most reliable things you can do to build muscle and strength. For most people training hard, 1.6–2.2 g per kg of bodyweight per day covers it — more than that doesn't add anything.
How to apply
- -Aim for roughly 1.6–2.2 g of protein per kg of bodyweight per day. For a 75 kg person that's about 120–165 g — most people land here by being deliberate at each meal, not by adding shakes.
- -Spread it across the day: 3–4 meals of 30–50 g protein each is easy to hit and covers the muscle-building bases.
- -Hit your daily total first. Whole foods (meat, fish, eggs, dairy, legumes) and supplements like whey are interchangeable — total intake matters far more than source or exact timing.
- -When dieting in a calorie deficit, keep protein at the high end (or slightly above) to protect muscle while losing fat.
Safety
- -More is not better past the point of return — studies show gains plateau around 1.6 g/kg/day, so chasing 3+ g/kg adds cost and food volume without extra muscle.
- -Bodyweight-based targets can overshoot for people carrying high body fat; in that case lean (fat-free) mass is a more sensible basis for the calculation.
- -Healthy kidneys handle high protein fine, but if you have diagnosed kidney disease, talk to your doctor before pushing intake up.
- -Protein only builds muscle when paired with resistance training and adequate total calories — eating more protein alone does little.
Key research
- A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adultsMorton RW et al., British Journal of Sports Medicine, 2018 · Meta-analysis
- International Society of Sports Nutrition Position Stand: protein and exerciseJäger R et al., J Int Soc Sports Nutr, 2017 · Position stand
- Dose-response relationship between protein intake and muscle mass increase: a systematic review and meta-analysis of randomized controlled trialsTagawa R et al., Nutrition Reviews, 2020 · Meta-analysis
- Synergistic Effect of Increased Total Protein Intake and Strength Training on Muscle Strength: A Dose-Response Meta-analysis of Randomized Controlled TrialsTagawa R et al., Sports Medicine - Open, 2022 · Meta-analysis
Related
Supplements
Educational information, not medical advice. Talk to a healthcare professional before starting a supplement — especially if you're pregnant, nursing, or managing a health condition.
Reviewed Jun 2026
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