← Home
Diet Doctor Podcast · August 22, 2022 · 40m
Protein Quality — Why Source Matters
Dr. Scher explores protein quality beyond total grams — DIAAS scoring, leucine thresholds, amino acid profiles, and why animal protein sources have higher bioavailability than most plant sources.
Highlights
•
DIAAS scoring reveals that plant proteins are 20-40% less bioavailable than animal proteins for muscle synthesis
Scher: the Digestible Indispensable Amino Acid Score (DIAAS) — the gold standard for protein quality — shows that most plant proteins score 40-75% while animal proteins score 90-120%. This means more total plant protein is needed to achieve the same muscle protein synthesis.•
The leucine threshold — 2.5-3g per meal triggers muscle protein synthesis, and some plant proteins fall short
Scher: muscle protein synthesis requires a leucine threshold of ~2.5g per meal in young adults and ~3g in older adults. Animal proteins naturally meet this threshold in a standard serving while many plant proteins require larger servings.