Macro partitioning
Increasing daily protein intake to ≥1.6 g/kg/day enhances lean body mass gains in healthy adults under 65 years old who perform resistance exercise, whereas older adults (≥65) achieve significant gains at lower intakes (1.2–1.59 g/kg/day).
If you are under 65 and lifting weights, aim for at least 1.6 grams of protein per kilogram of body weight daily to maximize muscle growth. If you are 65 or older, you may see significant muscle benefits with a slightly lower intake of 1.2 to 1.6 grams per kilogram. This assumes you are doing resistance exercise; protein alone without exercise has minimal impact on muscle mass in healthy adults.
The effect on LBM was significant in subjects ≥65 years old ingesting 1.2–1.59 g of protein/kg/day and for younger subjects (<65 years old) ingesting ≥1.6 g of protein/kg/day submitted to RE.
Why this rating
Based on 62 RCTs with moderate certainty of evidence (GRADE), though heterogeneity was low.
Source
Systematic review and meta‐analysis of protein intake to support muscle mass and function in healthy adults
Everson Araújo Nunes et al. · Journal of Cachexia Sarcopenia and Muscle · 2022
This is one finding among thousands. Every one is graded and traced to its source, so you can see what the evidence actually supports. Browse the research →