THE BOTTOM LINE

For muscle building: 1.6–2.2g per kg of bodyweight per day. For fat loss while preserving muscle: 1.8–2.4g/kg. For healthy adults over 40 or 50: 1.6–2.2g/kg (the upper end). The RDA (0.8g/kg) is insufficient for anyone training seriously or trying to preserve lean mass with age.

The Evidence Base

Meta-Analysis · Morton et al., 2018 — PMID 28698222

1.62g/kg/day is the upper inflection point for muscle building

Meta-analysis of 49 RCTs (n=1,863) found protein supplementation significantly increased lean mass during resistance training. The dose-response curve plateaued at ~1.62g/kg/day for lean mass gains. Consuming more isn't harmful — it just offers diminishing returns beyond this point for hypertrophy specifically.

Systematic Review · Stokes et al., 2018 — PMID 30018105

2.2g/kg/day is safe and supports body recomposition

Reviews of high-protein diets (2.0–3.4g/kg/day) in resistance-trained athletes find no adverse effects on kidney or liver function. Higher intakes (2.0–2.2g/kg) support simultaneous muscle building and fat loss, particularly in trained individuals.

Review · Phillips & Van Loon, 2011 — PMID 21367944

Older adults require more protein per meal than younger adults

Age-related anabolic resistance means muscle protein synthesis in adults 50+ responds less efficiently to amino acid ingestion. Higher protein per meal (40g vs 20g) produces greater MPS in older adults. The daily requirement remains similar but per-meal dosing strategy matters more.

Protein Recommendations by Goal

GoalRecommended RangeNotes
General health (sedentary)1.0–1.2 g/kg/dayAbove RDA; preserves muscle with aging
Recreational training1.4–1.6 g/kg/dayAdequate for most gym-goers
Muscle building1.6–2.2 g/kg/dayPlateau effect ~1.62 g/kg per meta-analysis
Fat loss (muscle preservation)1.8–2.4 g/kg/dayHigher protein protects LBM in caloric deficit
Adults 50+1.6–2.2 g/kg/dayHigher end preferred due to anabolic resistance
Competitive athletes1.6–2.2 g/kg/dayTiming and per-meal distribution matter more

How to Hit Your Protein Target

For a 80kg person targeting 2g/kg: 160g protein daily. Practical breakdown: 40g at breakfast (3–4 eggs + cottage cheese or protein shake), 50g at lunch (200g chicken breast or 200g canned tuna), 50g at dinner (200g salmon or 250g lean beef), 20g snack (Greek yogurt or protein shake). One whey protein shake adds 25g per scoop to your daily total.

Top Protein Supplements

ON Whey
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Dymatize ISO100
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FAQs

Can eating too much protein be harmful?

In healthy adults with normal kidney function, high protein intake (up to 2.8g/kg/day) has not been shown to cause kidney damage in RCTs. The concern originated from observational data in patients with pre-existing kidney disease, who do need protein restriction. For healthy individuals, protein excess is simply used for energy or converted to glucose — it doesn't damage kidneys.

How much protein can my body absorb per meal?

The "30g per meal" rule is outdated. Studies show muscle protein synthesis continues to rise up to 40–70g per meal in some contexts. The practical takeaway: there's a threshold effect — below ~3g leucine per meal, MPS isn't maximally stimulated. Above ~40g per meal offers diminishing returns for acute MPS. Over a full day, total protein matters most; per-meal distribution is secondary.

Use our protein intake calculator

Calculate your specific protein target with the Protein Intake Calculator → based on your bodyweight, goal, and activity level.

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→ Whey Protein Guide→ Protein Calculator→ Best Whey Proteins