Research

Hormonal

Postprandial plasma leucine concentration and ingested leucine dose are poor predictors of muscle protein synthesis (MPS) rates when protein is consumed as whole foods or mixed meals, indicating that leucine is not the sole or primary driver of the anabolic response in complex nutritional contexts.

Stop obsessing over hitting specific leucine targets with isolated powders. When you eat whole protein sources like eggs, meat, or dairy, your body handles the anabolic signaling effectively regardless of minor variations in leucine content. The food matrix and other nutrients play a crucial role that isolated leucine metrics miss.

GoodRefutesHIGH confidence
Our view is that recent evidence is driving a more nuanced picture of the regulation of postprandial MPS by revealing a compelling dissociation between ingested leucine or plasma leucinemia and the magnitude of the postprandial MPS response.
Alistair J. Monteyne et al. · American Journal of Clinical Nutrition · 2024

Why this rating

Based on multiple systematic reviews and direct experimental comparisons of whole foods vs. isolates, though mechanistic details of 'whole food effects' are still being elucidated.

Source

Reconsidering the pre-eminence of dietary leucine and plasma leucinemia for predicting the stimulation of postprandial muscle protein synthesis rates

Alistair J. Monteyne et al. · American Journal of Clinical Nutrition · 2024

DOI 10.1016/j.ajcnut.2024.04.032

narrative_reviewCited 14×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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 →