Protein Supplements: The Science-First Buying Guide 2026
🥛 Protein & amino acids
Protein Supplements: What the Research Shows
Protein supplementation is one of the most well-evidenced nutritional interventions in sports science. A 2018 British Journal of Sports Medicine meta-analysis of 49 studies (1,800 participants) confirmed that protein supplementation significantly increases muscle mass and strength gains from resista
1.6g/kg
Daily ceiling dose
25-40g
Per serving sweet spot
The science behind this category
Protein supplementation is one of the most well-evidenced nutritional interventions in sports science. A 2018 British Journal of Sports Medicine meta-analysis of 49 studies (1,800 participants) confirmed that protein supplementation significantly increases muscle mass and strength gains from resistance training — with a ceiling effect at approximately 1.6g per kg of bodyweight per day.
All reviews in this category
Every article cites peer-reviewed primary sources. Last updated July 2026.
Frequently asked questions
Is whey protein better than plant protein?
For muscle protein synthesis (MPS), whey protein has a slight edge due to its higher leucine content and faster absorption rate. However, a 2013 study found rice protein isolate produced equivalent lean mass gains to whey at matched doses. The gap largely disappears when plant protein is consumed at adequate total doses (1.6g/kg/day) and is well-combined for complete amino acid profiles.
When is the best time to take protein?
Protein distribution across the day matters more than timing. Consuming 0.4g/kg in 4 meals produces better MPS than 2 larger meals. The post-workout “anabolic window” is wider than often claimed — muscle protein synthesis remains elevated for 24–48 hours. Consuming protein within a few hours of training is sensible but not critical.
How much protein per day do I need?
The ISSN recommends 1.4–2.0g per kg of bodyweight daily for individuals engaged in resistance training. 1.6g/kg appears to be the approximate ceiling for muscle protein synthesis benefit, with diminishing returns above 2.2g/kg. Requirements are higher when in a caloric deficit.
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