Why your protein target should be closer to 2.5g/kg than 1g/kg

The most commonly repeated protein guideline — roughly 0.8 to 1g per kilogram of bodyweight — comes from research on preventing deficiency in sedentary adults. It's a floor, not a target, and it was never meant to describe anyone who trains regularly, is in a calorie deficit, or is trying to build or preserve muscle while losing fat.

What changes once training enters the picture

Resistance training increases the rate at which muscle protein breaks down and needs to be rebuilt. Being in a calorie deficit — which most people trying to change their body composition are — makes the body more likely to pull from muscle tissue for energy unless protein intake specifically protects against it. Both effects push the real requirement well above the sedentary-maintenance number.

This is where a target closer to 2 to 2.5g per kilogram of bodyweight comes from: it's the range where research on trained individuals in a deficit consistently shows the best muscle retention, without meaningfully higher benefits above it. Below roughly 1.6g/kg, most people training seriously start losing more muscle than necessary along with fat.

The practical takeaway

If a calculator or app gives you a protein target under 1.5g per kilogram and you train regularly, that number is doing you a disservice — it's protecting against deficiency, not supporting the actual goal of holding onto muscle while losing weight. Set the target based on what you're doing with your body, not on a guideline designed for someone who isn't training at all.