How Much Protein Do You Actually Need? The Science Without the Bro-Science
The supplement industry says 1 gram per pound. Your doctor says 50 grams total. The research lands somewhere in between, and the answer depends on what you are trying to do.
The Recommended Dietary Allowance (RDA) for protein is 0.36 grams per pound of body weight — about 56 grams for a 155-pound person. This number is frequently cited by doctors and nutritionists, and it is correct in the narrowest possible sense: it is the minimum intake to prevent protein deficiency in a sedentary person. It is not the optimal intake for anyone who exercises, wants to build muscle, is trying to lose weight, or is over 50. For those groups — which covers most adults who care about their health — the research supports significantly more.
What the Research Actually Shows
For muscle building: 0.7-1.0 grams per pound of body weight. A 2018 meta-analysis in the British Journal of Sports Medicine analyzed 49 studies and found that protein intake above 0.73 g/lb provided diminishing returns for muscle growth. Going from 0.4 to 0.7 g/lb made a large difference. Going from 0.7 to 1.0 g/lb made a small difference. Going above 1.0 g/lb made no measurable difference. The "1 gram per pound" rule is slightly higher than necessary but not harmful, and the round number makes it easy to remember.
For fat loss: 0.8-1.2 grams per pound of body weight — higher than maintenance, not lower. This sounds counterintuitive, but higher protein during a calorie deficit preserves muscle mass, increases satiety (you feel full longer on fewer total calories), and has a higher thermic effect (your body burns 20-30% of protein calories during digestion versus 5-10% for carbs and 0-3% for fat). In a calorie deficit, protein is the macro that protects everything you want to keep.
For general health over 50: 0.5-0.7 grams per pound. Sarcopenia (age-related muscle loss) accelerates after 50, and higher protein intake combined with resistance training is the most effective intervention. The standard RDA of 0.36 g/lb is particularly inadequate for older adults.
Calculate your exact protein target alongside carbs and fat with our macro calculator — it adjusts recommendations based on your age, weight, activity level, and goal.