Protein Intake Calculator

The RDA is 0.8 grams per kilogram of body weight, which is a minimum to prevent deficiency rather than an optimum. Active people generally do better at 1.2 to 1.6 g/kg, and 1.6 to 2.2 g/kg is the common recommendation for building muscle. For a 70 kg person that spans roughly 56 g to 154 g a day.

They are population averages drawn from studies with wide individual variation, and they are ranges for a reason. Research on muscle gain shows benefits mostly plateauing around 1.6 g/kg with little added return past 2.2 g/kg, but individual responses differ. Body weight is also a crude scaler — for people carrying substantial excess fat, calculating from lean body mass or a target weight gives a more sensible number.

In healthy adults, intakes up to around 2 g/kg have not been shown to harm kidney or bone health in controlled studies. People with existing kidney disease are a different case and should follow medical advice on protein restriction. Very high intakes also crowd out other foods, which has its own costs.

Lean mass is the more logical basis, since fat tissue has minimal protein requirement. For people in a normal weight range the difference is small; for someone with a high body-fat percentage, using total weight can overstate needs considerably.

The idea of a hard 20 to 30 gram per-meal ceiling is a misreading of the research — the body absorbs almost all dietary protein, just more slowly with larger doses. Spreading intake across three to four meals is a reasonable practice, but a large single serving is not wasted.