When athletes are trying to lose weight by eating fewer calories, eating more protein (about 2.3 grams per kilogram of body weight) helps them keep more of their muscle compared to eating less...

If young guys lift weights hard and do intense workouts while eating less for a month, chugging 2.4 grams of protein per pound of muscle each day helps them gain more muscle and lose more fat than eating half that much protein.

For young men who exercise regularly, eating more than 2.0 grams of protein per kilogram of body weight per day does not lead to significantly more muscle gain than eating less than that amount over an 8-week resistance training program.

If you're someone who lifts weights and isn't overweight, eating more protein while cutting calories helps you keep more muscle — especially if you base your protein needs on how much muscle you have, not your total weight.

If you're an untrained adult with extra weight, doing resistance training for 12 weeks while eating less—either through intermittent fasting or cutting calories every day—and getting enough protein, gives you similar gains in muscle, strength, and fat loss, no matter which diet approach you pick.

If young guys eat more protein while working out hard and cutting calories for a month, they’ll gain more muscle and lose more fat compared to eating less protein.