Nutrition
As of 2026-04-24
How Protein Intake Calculator works
Methodology for the Protein Intake Calculator: formulas, coefficients, data sources, assumptions, and known limitations.
Scope
Reports a daily protein target in grams based on bodyweight and goal (general health, hypertrophy, fat loss, older adult).
Formula
protein_target_g = bodyweight_kg x multiplier_for_goal.
Coefficients
| Parameter | Value | Note |
|---|---|---|
| General health | 0.8–1.2 g/kg/day | |
| Hypertrophy | 1.6–2.2 g/kg/day | |
| Fat loss (preserve LBM) | 2.2–2.6 g/kg/day | |
| Older adult (sarcopenia prevention) | 1.2–1.6 g/kg/day |
Data sources
- Morton RW, Murphy KT, McKellar SR, et al. A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults. Br J Sports Med. 2018;52(6):376-384. — PMID 28698222. Supports the 1.6–2.2 g/kg/day hypertrophy range.
- Phillips SM, Chevalier S, Leidy HJ. Protein 'requirements' beyond the RDA: implications for optimizing health. Appl Physiol Nutr Metab. 2016;41(5):565-572. — PMID 26960445.
- Bauer J, Biolo G, Cederholm T, et al. Evidence-based recommendations for optimal dietary protein intake in older people: a position paper from the PROT-AGE Study Group. J Am Med Dir Assoc. 2013;14(8):542-559. — PMID 23867520. Source of the sarcopenia-prevention range.
- Jäger R, Kerksick CM, Campbell BI, et al. International Society of Sports Nutrition Position Stand: protein and exercise. J Int Soc Sports Nutr. 2017;14:20. — PMID 28642676. ISSN consensus on protein intake for active adults.
Assumptions
- Protein is distributed across 3–5 meals; total per day is the metric that matters.
Approximation range
Hypertrophy response plateaus above ~1.6 g/kg/day; diminishing returns above 2.2 g/kg/day in non-deficit conditions.
Limitations
- Does not adjust for kidney disease — people with CKD should follow clinical guidance, not this tool.
- High-protein intakes are safe for healthy adults per current evidence, but the tool cannot see medical history.
Reproducibility
Hypertrophy, 85 kg: 85 * 1.6 = 136 g; 85 * 2.2 = 187 g. Range 136–187 g/day.
Change log
- 2026-04-24: methodology page first published.
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