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Protein intake

Strong evidence
MuscleStrength

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

Related

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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