To build muscle, your body needs a certain amount of protein each day. Scientists have figured out that amount is about 2.2 grams for every kilogram you weigh, using a test that shows how your body processes protein.
See the scientific wording
The dietary protein requirement for muscle protein synthesis is estimated at 2.2 grams per kilogram of body weight per day, based on indicator amino acid oxidation measurements.
There's disagreement
The 2 studies we reviewed point in different directions — there's no clear consensus.
What the research says
2 studies reviewedSupporting (1)
Evaluation of dietary protein and amino acid requirements: a systematic review.
Systematic ReviewReview2025
Scientists reviewed many studies on protein needs and found that some newer tests suggest we might need more protein, like about 2.2 grams per kilogram of body weight each day, instead of the old 0.8 grams.
Contradicting (1)
Randomized Controlled TrialHuman2015
The study says you need about 1 gram of protein per kilogram of body weight, but the claim says 2.2 grams, so the study disagrees.
Quality-weighted scoring: we follow the GRADE framework — each study is rated High, Moderate, Low, or Very Low based on study design, methodology rigor, and risk of bias. A single high-quality RCT can outweigh several weaker observational studies.
Scores reflect study quality, not just count.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting, 1 contradicting studies
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