How Much Protein Do You Actually Need?

Most nutrition labels point to 50g per day as the daily value for protein. Most gym-goers think that number is laughably low. They're right — but the real target depends almost entirely on your body weight, your age, and what you're training for.

The Official Recommendation — And Why It Falls Short

The Recommended Dietary Allowance (RDA) for protein is 0.8g per kilogram of body weight per day. For a 75kg person, that's just 60g. The problem: the RDA is designed as a minimum to prevent deficiency in sedentary adults — not as an optimal target for someone who trains, wants to build muscle, or is actively losing fat.

Using the RDA as your protein goal when you train regularly is like using the speed limit in a car park as your highway target. Different context, different requirement.

What the Research Says for Active People

A landmark 2017 meta-analysis published in the British Journal of Sports Medicine (Morton et al.) pooled data from 49 studies and over 1,800 participants. The finding: muscle gains from resistance training plateaued at approximately 1.62g of protein per kg of body weight per day. Benefits beyond roughly 2.2g/kg were negligible for most people.

For the majority of people who train consistently, the evidence points to a daily target of 1.6–2.2g/kg as the optimal range.

How Your Goal Changes the Number

Your training goal shifts where in that range you should aim — and sometimes pushes you above it:

• Building muscle (bulking): 1.8–2.2g/kg — supports maximal muscle protein synthesis with a caloric surplus
• Losing fat (cutting): 2.0–2.4g/kg — higher protein during a deficit preserves lean muscle and keeps you fuller
• Athletic performance: 1.6–1.8g/kg — sufficient to support recovery without adding unnecessary calories
• Maintaining weight: 1.4–1.8g/kg — enough to maintain lean mass with regular training

Age and Protein: Why It Gets More Important Over Time

After roughly age 50, the body becomes less sensitive to protein's muscle-building signal — a well-documented process called anabolic resistance. Older adults often need a larger dose of protein per meal (35–40g rather than 20–25g) to trigger the same degree of muscle protein synthesis.

For active people over 50, most sports nutrition researchers recommend staying at the higher end of the range — around 1.8–2.2g/kg — and distributing that protein across at least 3–4 meals per day.

The Simple Calculation

Multiply your body weight in kilograms by your target per-kg intake. If you weigh 80kg and your goal is to build muscle: