The Muscle Protein Synthetic Response to the Ingestion of a Plant-Derived Protein Blend Does Not Differ from an Equivalent Amount of Milk Protein in Healthy Young Males.
Level 2 - randomized trial
Individual randomized controlled trial
PubMed 36170964 · doi:10.1093/jn/nxac222
What was done
In a randomized, double-blind, parallel-group trial, 24 healthy young men (mean age 24 ± 4 years) received a primed continuous L-[ring-13C6]-phenylalanine infusion before ingesting either 30 g of milk protein or a 30 g plant protein blend containing 15 g wheat, 7.5 g corn, and 7.5 g pea protein. Frequent blood samples and muscle biopsies were obtained over a 5-hour postprandial period to measure plasma amino acid concentrations and myofibrillar protein synthesis rates.
What was found
Milk protein ingestion produced a significantly larger increase in plasma essential amino acid incremental AUC over 5 hours compared to the plant blend (151 ± 31 vs 79 ± 12 mmol·300 min·L-1, P < 0.001). Both milk protein and the plant blend significantly increased myofibrillar protein synthesis rates (P < 0.001), with no statistically significant difference between milk (0.053 ± 0.013%/h) and the plant blend (0.064 ± 0.016%/h, P = 0.08).
Why it matters
Strategic blending of complementary plant proteins can overcome single-source amino acid limitations and induce acute resting muscle protein synthesis comparable to high-quality dairy protein.
Limits
The study evaluated only acute 5-hour responses to a single resting dose without testing chronic exercise training adaptations or muscle hypertrophy. The sample was small (n = 24 across two parallel groups) and restricted to healthy young men, limiting generalizability to females, older populations, or athletes.
Cited by
- supports Most plant-based proteins are deficient in one or more specific essential amino acids, most commonly methionine and lysine.
- supports Giving healthy subjects 30 grams of protein extract from pea, gluten, or corn stimulates muscle protein synthesis to a degree not significantly different from dairy protein.