Formula, in Nutrition Planning

Protein Intake Formula

Set protein by lean body mass when you have it; otherwise by total body mass. 1.6–2.2 g/kg covers nearly every training context. Above 2.4 g/kg, returns flatten.

3 variables. Published Mar 12, 2026. Updated May 10, 2026. By AI Fit Hub.

Education, not medical advice. The result comes only from the published formula and your inputs. How we check our formulas.

Formula

protein_g = mass_kg × goal_factor
(use LBM_kg × 2.0 when body-fat percentage is known and elevated)

Variables

protein_g

Daily protein target

Grams per day. Distribute across 3–5 feedings, each containing at least 0.3 g/kg to saturate muscle protein synthesis.

mass_kg

Body mass

Kilograms. Use lean mass when BF% > 25% to avoid over-targeting fat tissue.

goal_factor

Protein factor

0.8 sedentary RDA, 1.4–1.6 active baseline, 1.8 hypertrophy or modest deficit, 2.0–2.2 aggressive cut or aging-related anabolic resistance.

Step by step

1

Pick the factor that matches the training context, not the aspiration.

Recreational lifter in a 15% deficit → 1.8 g/kg.
2

Multiply by body mass in kilograms (or lean body mass in kilograms for elevated BF%).

78 kg × 1.8 = 140.4 g protein.
3

Divide by 4 to estimate feedings of ≥0.3 g/kg each (the MPS-saturating threshold).

78 × 0.3 = 23.4 g per feeding minimum. 140.4 / 23.4 = 6 feedings if you maxed out each; practical layout is 4 feedings of ~35 g.
4

Anchor leucine: each protein feeding should provide 2.5–3 g leucine. Whey, eggs, beef, and soy isolate hit this in 25–30 g servings. Plant proteins often need a larger portion to match.

1 scoop whey (25 g protein) supplies ~2.5 g leucine; 2 large eggs (12 g protein) supplies ~1.0 g.

Worked example

78 kg adult, 1.8 g/kg target

Body mass (kg)

Goal factor

1.8 (deficit / hypertrophy)

protein_g = 78 × 1.8 = 140.4 g/day

Daily protein 140 g, spread across 4 feedings of ~35 g (leucine-saturating). 562 cal from protein.

Common variations

Older adults (>60) benefit from 2.0–2.4 g/kg due to anabolic resistance.

Endurance athletes during heavy training weeks: 1.4–1.6 g/kg is sufficient; extra protein displaces carbs that fuel work.

Plant-forward diets: aim 15–20% higher (~2.0 g/kg) to compensate for lower digestibility (DIAAS) of most plant proteins.

Run the numbers next

Nutrition Macro Calculator
Convert calorie targets into protein, carbs, and fat grams for your goal.
Body Composition Lean Body Mass Calculator
Estimate lean body mass using Boer, James, and Hume formulas from height and weight.

Sources

Morton RW 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 , British Journal of Sports Medicine (2018)
Phillips SM, Van Loon LJ. Dietary protein for athletes: from requirements to optimum adaptation , Journal of Sports Sciences