Details up front: 68 kg · 1,200 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?
109 to 150 g a day. The range the resistance-training literature supports is 1.6 to 2.2 g per kilogram, which at 68 kg is 109–150 g. At 4 kcal per gram that is 435–598 kcal, or 36–50 per cent of a 1,200 intake — which is why protein has to be planned first at this energy level rather than fitted in afterwards. Split it across three or four servings; roughly 0.4 g/kg per meal saturates the synthetic response and the surplus in one large serving does not carry over.
Answer first: aim for 1.6 to 2.2 grams per kilogram of reference body weight per day, distributed across three or four servings, and treat it as the first constraint on the day rather than the last.
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.
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.
Systematic reviews of high-protein intake in people with normal renal function have not found evidence of harm to kidney function.
1.6 to 2.2 g/kg of reference weight, split three or four ways. That is the answer.
edited 24 Sept 2025 by amara_nwachukwu — reworded for clarity after a comment
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Visit GL BiochemThe honest answer is that most people in a deficit fall well short, and closing that gap matters more than any refinement above it.
Use reference or adjusted body weight rather than total weight where adiposity is substantial: a common approach is ideal body weight plus a quarter of the excess, which avoids targets that no one could eat.
Concretely, 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.
Targets are population estimates; individual requirements vary and there is no cheap way to measure yours.
Plan protein first in the day; with suppressed appetite it will not happen otherwise.
Put another way, 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.
Hydration requirements rise modestly with protein intake because urea excretion increases, which is a real effect and a small one.
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.
On the detail: protein is also the most satiating macronutrient per kilocalorie, which makes hitting the target easier than it sounds once it is prioritised.
Older adults need more per meal to overcome anabolic resistance, with 1.2 to 1.5 g/kg daily commonly quoted for maintenance and more in a deficit.
Research-use compounds are not approved for human use, and no supplement substitutes for total intake.
Healthy kidneys tolerate this fine. Diseased ones are a clinical question.
Put another way, plant-based patterns need somewhat higher totals and more attention to leucine content per serving to produce an equivalent response.
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.
Meta-analytic estimates place the plateau of the dose-response for lean-mass retention with resistance training around 1.6 g/kg, with a confidence interval extending to about 2.2.
The caveat is that anyone with chronic kidney disease has a genuinely different protein calculation and needs it done by a clinician.
Plant-based patterns need a higher total and more attention per serving.
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