How much protein in grams do I need at 62 kg on 800 kcal a day?

Numbers first: 62 kg · 800 kcal.

This should be a straightforward calculation and I keep getting two different answers.

The numbers are arbitrary; the method is what I am after.

What is the general form of this calculation?

The short version: total daily protein first, per-meal distribution second, timing a distant third.

A practical construction: 30 to 40 grams at each of three meals plus a 20 to 30 gram snack covers most targets without any protein powder at all.

It helps to be literal here: high protein intakes do not damage healthy kidneys in the published evidence; existing kidney disease is a genuine exception and is a clinical question.

Stable-isotope feeding studies establish the per-meal saturation of muscle protein synthesis at around 0.4 g/kg in young adults and higher in older ones.

Per-meal saturation is real. One enormous serving does not do the job of three.

edited 8 Apr 2025 by claudia_ferrante — updated for the 2026 guidance change

Start with which body weight the target is calculated from, because using total weight in someone with substantial adiposity inflates the number without benefit.

The leucine threshold for triggering the response is around two and a half to three grams per meal. Thirty grams of most animal protein reaches it; thirty grams of many plant proteins does not, which is why plant-based targets run higher.

More usefully, hydration requirements rise modestly with protein intake because urea excretion increases, which is a real effect and a small one.

Systematic reviews of high-protein intake in people with normal renal function have not found evidence of harm to kidney function.

The caveat is that anyone with chronic kidney disease has a genuinely different protein calculation and needs it done by a clinician.

Plan protein first in the day; with suppressed appetite it will not happen otherwise.

edited 8 Apr 2025 by s_kalniete — tightened the wording; no substantive change

The part that matters: the relevant physiology is the per-meal saturation of the synthetic response, which is why one large serving does not substitute for three moderate ones.

Per meal, roughly 0.4 grams per kilogram saturates the synthetic response in most adults, which is about 30 to 40 grams for a typical person. Beyond that the surplus is oxidised or used for other purposes rather than adding to synthesis.

Leucine threshold effects are documented across protein sources and explain the difference in per-serving requirements between animal and plant proteins.

Plant-based patterns need a higher total and more attention per serving.

Put another way, protein is also the most satiating macronutrient per kilocalorie, which makes hitting the target easier than it sounds once it is prioritised.

Appetite suppression makes protein-rich foods harder to eat because they are satiating. Liquid protein and leaner, less voluminous sources are the usual practical workaround.

The body-composition substudies in the major programmes consistently report that the proportion of weight lost as fat mass is approximately three quarters or better, with the lean-mass fraction falling within the range seen in dietary weight loss of comparable magnitude[1].

Healthy kidneys tolerate this fine. Diseased ones are a clinical question.