Protein per Day by Weight

Daily protein intake per body weight

Protein targets are almost always written as grams per kilogram of body weight per day. The math behind it is protein_g/day = factor × weight_kg. What changes is the factor, and that depends on how active you are, what you're training for, your age and any clinical condition you might have.

Some reference ranges to anchor the factor: sedentary adults sit around 0.8 g/kg (RDA, IOM), physically active people land at 1.2–1.6 g/kg, and anyone chasing hypertrophy through resistance training pushes that up to 1.6–2.2 g/kg (ISSN Position Stand, Jäger et al., 2017). Older adults facing a risk of sarcopenia do well on 1.0–1.2 g/kg (PROT-AGE Study Group), while patients under surgical stress or sepsis may need 1.5–2.0 g/kg (ESPEN guidelines).

Applications

It comes up in sports nutrition planning, in lean-mass protocols, in weight-loss diets built to spare muscle, when checking whether an older person's diet is adequate, and during post-operative recovery. Where does the protein come from? Eggs, chicken, fish, lean beef, dairy, legumes like beans, lentils and chickpeas, tofu, and whey protein supplements (regulated in Brazil by ANVISA RDC 243/2018 and 269/2005).

FAQ

Can high-protein diets harm the kidneys? For healthy adults, long-term studies haven't found adverse renal effects at intakes up to 2.2 g/kg/day. Anyone with chronic kidney disease is a different story and needs to follow medical guidance.

Should I split protein across meals? It helps. Spreading 0.3–0.4 g/kg over 3–4 meals keeps you above the leucine threshold each time, which is what drives muscle protein synthesis.

Does this calculator replace a nutritionist? No. The numbers here are educational estimates drawn from scientific literature (ISSN, SBME, ANVISA). An individual prescription still has to come from a registered dietitian or physician.