The Claim

Adding 1.5 grams of leucine to a 20-gram pea-and-canola plant protein blend increases plasma leucine concentration by approximately 42% and muscle protein synthesis by 16% compared to the unfortified blend in young adults, demonstrating that leucine is a limiting amino acid in this plant protein formulation.

Source: Muscle Protein Synthesis in Response to Plant-Based Protein Isolates With and Without Added Leucine Versus Whey Protein in Young Men and Women

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
66score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

Cause and effect
1 study reviewed
In plain English

Adding a little extra leucine to a plant-based protein shake makes your body absorb more leucine and builds more muscle compared to the shake without it, which means leucine was the missing piece your body needed.

See the scientific wording

Adding 1.5 grams of leucine to a 20-gram pea-and-canola plant protein blend increases plasma leucine concentration by approximately 42% and muscle protein synthesis by 16% compared to the unfortified blend in young adults, demonstrating that leucine is a limiting amino acid in this plant protein formulation.

What the research says

1 study
  1. Study: Muscle Protein Synthesis in Response to Plant-Based Protein Isolates With and Without Added Leucine Versus Whey Protein in Young Men and Women

    Adding extra leucine to plant-based protein helps your muscles grow better, just like animal proteins do. Without it, plant proteins aren’t as good at building muscle — but adding leucine fixes that.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

Fit Body Science verdict — we translate health claims into clear verdicts backed by peer-reviewed research.

Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.