Protein Per Meal Calculator

Why per-meal protein has its own number

Muscle protein synthesis is triggered rather than accumulated. Roughly 0.25 g of protein per kg of bodyweight in a single meal, supplying about 2.5 to 3 g of leucine, maximally stimulates the response. Beyond that the extra protein is used for other purposes rather than producing a proportionally larger signal.

This is why distribution matters. Three feedings of 30 g stimulate synthesis three times; 90 g eaten at once stimulates it once. Research on protein distribution has found meaningfully greater daily synthesis from an even spread than from a dinner-heavy pattern.

The calculator raises the per-meal figure with age. Anabolic resistance means older adults need a larger dose to trigger the same response, which is why the recommendation moves from around 0.25 g per kg in young adults toward 0.4 g per kg past 60. It also raises the target for mostly plant-based eaters, since plant proteins carry less leucine per gram.

The per-meal calculation

The underlying requirement is leucine, not protein as such. Roughly 2.5 to 3 g of leucine in a single serving appears necessary to maximally trigger muscle protein synthesis. Because protein sources differ in leucine content, the gram target differs by source.

Leucine content by protein source

Anabolic resistance, and why age raises the number

Older muscle responds less strongly to the same protein dose, a phenomenon termed anabolic resistance. Research comparing younger and older men found older adults required a greater relative dose to maximally stimulate synthesis, which is why the per-meal figure rises with age rather than falling.

This has a practical consequence that runs against common advice. Appetite tends to decline with age, and older adults often eat lighter meals, particularly breakfast. That is precisely the wrong direction. Sarcopenia, the progressive loss of muscle with age, is driven partly by this mismatch, and adequate per-meal protein combined with resistance training is the main countermeasure.

Per-meal target by age and bodyweight

Hitting the number at each meal

Spacing and the refractory period

After a protein feeding, synthesis rises within about thirty minutes, peaks around one to two hours and returns toward baseline within three to five hours, even when amino acids remain elevated in the blood. That refractory pattern is the reason meals spaced three to four hours apart are commonly recommended, and why grazing continuously on small amounts of protein is less effective than distinct feedings.

The overnight gap is the longest period without protein, which is the rationale behind pre-sleep protein of 30 to 40 g. It is a refinement worth a few percent once your daily total and distribution are already consistent.

Frequently asked questions

Sources

• Moore DR et al. Protein ingestion to stimulate myofibrillar protein synthesis requires greater relative protein intakes in healthy older versus younger men. Journals of Gerontology, 2015.
• Mamerow MM et al. Dietary protein distribution positively influences 24-h muscle protein synthesis. Journal of Nutrition, 2014.
• Jager R et al. ISSN Position Stand: protein and exercise. JISSN, 2017.
• Witard OC et al. Myofibrillar muscle protein synthesis rates subsequent to a meal in response to increasing doses of whey protein. American Journal of Clinical Nutrition, 2014.
• National Institutes of Health, Office of Dietary Supplements. Nutrient fact sheets. ods.od.nih.gov
• NHS. Nutrition and health guidance. nhs.uk
• US Departments of Agriculture and Health and Human Services. Dietary Guidelines for Americans, 2025-2030. dietaryguidelines.gov

More tools: all calculators · Full Plan · Recomp · Body fat · Macros · Cheapest whey per 20 g

General information, not medical advice. Consult a qualified professional before changing your diet, especially with a medical condition.