Mixed
Consuming dietary protein at 1.6 g/kg/day (2x RDA) during a 40% energy deficit preserves fat-free mass and maintains muscle protein synthesis sensitivity to feeding, whereas 2.4 g/kg/day (3x RDA) provides no additional fat-free mass protection.
If you are losing weight, aim for 1.6 grams of protein per kilogram of body weight daily. This amount is sufficient to protect your muscle mass while you lose fat. Eating significantly more (e.g., 2.4 g/kg) does not provide additional muscle protection and may be unnecessary. Ensure you are in a moderate caloric deficit and maintain your usual activity level.
The proportion of weight loss due to reductions in fat-free mass was lower (P<0.05) and the loss of fat mass was higher (P<0.05) in those receiving 2x-RDA and 3x-RDA compared to RDA... consuming dietary protein at levels exceeding the RDA may protect fat-free mass during short-term weight loss... consuming dietary protein at levels beyond twice the current RDA fail to confer further FFM protection during short-term weight loss.
Why this rating
Randomized controlled trial with metabolic ward control, though short duration (21 days ED) and specific population (healthy, active adults).
Source
Effects of high‐protein diets on fat‐free mass and muscle protein synthesis following weight loss: a randomized controlled trial
Stefan M. Pasiakos et al. · The FASEB Journal · 2013
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