Research

Hormonal

Consumption of branched-chain amino acids (BCAAs) alone does not stimulate muscle protein synthesis or produce an anabolic response in humans; instead, it decreases muscle protein synthesis and turnover.

Taking BCAAs by themselves will not build muscle or increase protein synthesis in humans. In fact, studies show it may actually slow down muscle protein turnover. To build muscle, you need a complete protein source containing all essential amino acids, not just BCAAs.

GoodRefutesHIGH confidence
We conclude that the claim that consumption of dietary BCAAs stimulates muscle protein synthesis or produces an anabolic response in human subjects is unwarranted.
Robert R. Wolfe · Journal of the International Society of Sports Nutrition · 2017

Why this rating

Based on a review of human intravenous infusion studies showing decreased synthesis, though oral studies are lacking.

Source

Branched-chain amino acids and muscle protein synthesis in humans: myth or reality?

Robert R. Wolfe · Journal of the International Society of Sports Nutrition · 2017

DOI 10.1186/s12970-017-0184-9

narrative_reviewCited 327×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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