Research

Hormonal

Micellar casein provides a sustained, slow-release amino acid profile, whereas free L-amino acids (L-AAs) and casein glycomacropeptide (CGMP) result in rapid, transient absorption peaks.

If you want a slow, steady drip of amino acids (like before bed or during long fasting windows), choose micellar casein. If you need a rapid spike of amino acids (like immediately post-workout), free amino acids or CGMP will deliver them much faster than casein. Note that CGMP does not act like casein despite being a peptide.

GoodSupportsHIGH confidence
There was a consistent delivery of AAs for casein demonstrated by a sustained curve, but the absorption curves for L-AAs and CGMP were transient, rising rapidly and falling... Amino acids from CGMP and L-AAs were absorbed more rapidly than casein, inferring CGMP did not mimic casein, a slow-release protein source.
Anne Daly et al. · Nutrients · 2025

Why this rating

Randomized controlled crossover trial with healthy volunteers, though limited to 240 minutes and not measuring labeled protein synthesis directly.

Source

Protein Substitute Absorption: A Randomised Controlled Trial Comparing CGMP vs. Amino Acids vs. Micellar Casein in Healthy Volunteers

Anne Daly et al. · Nutrients · 2025

DOI 10.3390/nu17162671

crossover · n=20Cited 1×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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