There's a number most people carry around without ever questioning it. Somewhere between a nutrition label, a doctor's offhand comment, and a half-remembered search result, a protein target settled in: roughly 50 to 60 grams a day. The source felt official. The box felt checked.
The Recommended Dietary Allowance — 0.8 grams of protein per kilogram of body weight — was designed to answer one question: how little can a healthy adult eat without becoming deficient? A floor to prevent a shortage, not a target to preserve muscle. And if you don't lift weights, that distinction changes everything about the number you actually need.
How Much Protein Do Non-Lifters Actually Need?
The evidence from clinical trials in non-exercising adults told a sharply different story. The groups eating around 1.2 grams per kilogram — roughly 60% above the government's number — preserved about half a kilogram more muscle. They lost nearly a full kilogram more fat. Their resting metabolism stayed roughly 140 calories a day higher. No weights. No gym membership. Just protein.
Adults who don't lift weights preserve more muscle, lose more fat, and maintain a faster resting metabolism eating 1.2 to 1.6 grams of protein per kilogram of body weight per day — roughly double the government's Recommended Dietary Allowance of 0.8 g/kg. For a 70 kg person, that translates to 84 to 112 grams daily instead of 56.
— Wycherley et al. 2012 · n=1,063 across 24 RCTs; confirmed by Phillips 2026
1.2 to 1.6 grams per kilogram per day. The range where muscle preservation happens without lifting — and the figure the field's most-cited protein researcher recommends for most adults. His point is specific: the range covers lifters and non-lifters in the same breath, from the person deadlifting five mornings a week to the person whose workout is a long walk after dinner.
Those results come with an honest footnote. Protein makes a meaningfully bigger difference when paired with resistance training. Without lifting, the benefit is preserved muscle, lost fat, faster metabolism — and researchers call it modest. If you're over 40, the equation shifts further: aging muscle becomes less efficient at using protein, which means you need more per meal just to hold steady.
For a 70-kilogram person (about 154 pounds), that range means roughly 84 to 112 grams of protein a day. For someone at 80 kilograms (176 pounds), 96 to 128 grams. The RDA puts those same people at 56 to 64 grams. The gap between what prevents a deficiency and what preserves muscle is close to double.
The protein conversation was never only for people who don't lift.
You were in it all along — carrying a number that was built to keep you from a shortage, not to keep your muscle from quietly disappearing.
Half a kilogram of muscle, almost a full kilogram of fat, and a metabolism running 140 calories faster — from protein alone, without a single training session. The evidence on what protein does when resistance training enters the picture makes the case even harder to ignore.