How Much Protein Do I Need Per Day?

Protein for fat loss — why you need more, not less

During a calorie deficit, your body is under pressure to break down tissue for energy. Without sufficient protein, a significant portion of weight lost comes from muscle rather than fat — a phenomenon called lean mass catabolism.

Research consistently shows that higher protein intake (2.2–2.4 g/kg) during a cut:

• Preserves significantly more muscle mass compared to lower protein intakes
• Increases satiety, making it easier to maintain the calorie deficit
• Has a higher thermic effect (~25–30% of protein calories burned in digestion vs ~5–10% for carbs)
• Helps maintain metabolic rate by preserving lean mass

Protein for muscle gain — how much is enough?

The research consensus for maximising muscle protein synthesis (MPS) in natural trainees is 1.6–2.2 g/kg bodyweight per day. There is no evidence that intakes above 2.2 g/kg produce additional muscle growth — though they are not harmful for most healthy adults.

More important than hitting a large daily total is distributing protein across 3–5 meals. Each protein-rich meal triggers a pulse of MPS lasting 3–5 hours. Once MPS returns to baseline, another protein-rich meal is needed to trigger the next pulse.

For a natural trainee in a lean bulk, realistic muscle gain rates are 0.25–0.5 lbs/week for beginners and 0.1–0.25 lbs/week for intermediate-advanced lifters. Protein above the optimal range does not accelerate this ceiling.

Protein needs for women vs men

The fundamental mechanism of protein — supporting muscle protein synthesis and preservation — is identical for men and women. The difference is in absolute amounts (determined by bodyweight) rather than any metabolic gender difference.

Protein for women

Women generally weigh less than men, so absolute protein targets are proportionally lower. However, g/kg targets are the same: 1.6–2.2 g/kg for active women. Many women significantly under-eat protein — population surveys show average protein intake for women is approximately 68 g/day, well below the optimal 100–140 g/day for active women weighing 55–65 kg.

Women over 40 should pay particular attention to protein intake, as oestrogen decline with menopause reduces muscle protein synthesis efficiency — making adequate protein even more important for maintaining lean mass and bone density.

Protein for men

Men typically have more lean body mass, which drives higher absolute protein requirements. A 90 kg active male needs approximately 144–200 g/day — roughly twice the absolute amount of a 65 kg active female at the same g/kg target. Higher muscle mass also responds more dramatically to protein intake, making tracking more impactful for men at the extremes of body composition.

Protein needs for adults over 65

Older adults experience anabolic resistance — a reduced sensitivity to protein's muscle-building signal. A 70-year-old needs more protein per meal (35–40 g) to trigger the same MPS response a 25-year-old gets from 20–25 g. Research recommends 1.8–2.4 g/kg for adults over 65 to counteract age-related muscle loss (sarcopenia). Spacing protein evenly across 3–4 meals is particularly important for this age group.

High-protein food sources

The most practical way to hit a high protein target is combining animal and plant sources. Here are the highest-protein foods per 100g and per serving:

Animal protein sources

Plant protein sources

Values are approximate and vary by brand and preparation method.

Frequently asked questions about protein

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Results are estimates based on validated formulas. Not medical advice.