Protein: How Much You Actually Need
The official minimum and the useful target are different numbers, and the gap between them explains most of the internet argument.
Protein arguments go badly because two different questions get conflated. "How much do I need to avoid deficiency" and "how much is optimal for building and keeping muscle" have different answers, and both sides of most arguments are correct about the question they are answering.
The RDA is a floor
The Recommended Dietary Allowance is 0.8 g/kg of bodyweight per day. It is derived from nitrogen balance studies and it represents the amount sufficient to prevent deficiency in nearly all healthy adults.
It is a minimum for avoiding a deficit. It was never intended as a target for maximising muscle protein synthesis, and reading it that way is the source of a lot of confusion.
What the training literature says
The most useful reference point is the 2018 meta-analysis by Morton and colleagues in the British Journal of Sports Medicine, pooling 49 studies of protein supplementation with resistance training.
Two findings matter:
- Higher protein intake produced greater gains in lean mass and strength than lower intake, alongside resistance training.
- Benefits plateaued at approximately 1.6 g/kg per day, with the confidence interval extending to around 2.2 g/kg.
For an 80kg person that is about 130g per day.
The cases for going higher
Fat loss. In a calorie deficit, higher protein — often cited around 2.0-2.4 g/kg — better preserves lean mass. Protein is also the most satiating macronutrient and has the highest thermic effect, both of which help adherence.
Older adults. Anabolic resistance means ageing muscle responds less to a given protein dose. Higher intakes, in the region of 1.2-1.6 g/kg, are increasingly recommended for older adults specifically to counter this — and the RDA is arguably too low for this group.
Plant-based diets. Plant proteins are generally lower in leucine and less digestible. A modest upward adjustment, plus attention to variety across the day, is reasonable.
What does not matter as much as claimed
The anabolic window. The idea that protein must arrive within an hour of training does not survive the evidence. Total daily intake dominates; timing effects are small.
The 30g-per-meal ceiling. The claim that the body cannot use more than about 30g at a sitting is a misreading. Muscle protein synthesis response does saturate around that range, but larger doses are still digested, still absorbed, and still contribute to daily totals — and recent work on very large single doses shows prolonged utilisation.
Powder versus food. Convenience differs. Outcomes do not, when total intake and protein quality match.
Kidney concerns
In people with healthy kidneys, high protein intake has not been shown to cause renal damage. This has been examined repeatedly, including in long-term studies of athletes. In people with existing chronic kidney disease, protein restriction is a genuine clinical consideration — the advice applies to that population and got generalised to everyone.
A practical target
Aim for 1.6 g/kg, spread across three or four meals, each containing a decent protein source. If you are dieting or over sixty, aim higher. If you are sedentary and simply want to avoid deficiency, the RDA is fine and you can stop reading protein arguments entirely.
Not medical advice. If you have kidney disease, protein intake is a conversation for your nephrologist.
