Casein glycomacropeptide is well tolerated in healthy adults and changes neither high-sensitive C-reactive protein, gut microbiota nor faecal butyrate: a restricted randomised trial

Abstract

Casein glycomacropeptide (CGMP) is a bioactive milk-derived peptide with potential anti-inflammatory effects. Animal studies suggest that CGMP may work by altering gut microbiota composition and enhancing butyrate production. Its effects on intestinal homeostasis, microbiota and metabolites in humans are unknown. The aim of the present study was to assess both the intestinal and systemic immunomodulatory effects of orally ingested CGMP. We hypothesised that a daily oral CGMP intake would reduce high-sensitive C-reactive protein in healthy adults. In a single-centre limited but randomised, double-blinded, reference-controlled study, we compared the effects of a four-week intervention of either 25 grams of oral powder-based chocolate-flavoured CGMP or a reference drink. We included twenty-four healthy adults who all completed the study. CGMP had no systemic or intestinal immunomodulatory effects compared with a reference drink, either with regard to high-sensitive C-reactive protein, or faecal calprotectin level, faecal microbiota composition or faecal short-chain fatty acid content. CGMP ingestion did not affect satiety or body weight, and it caused no severe adverse events. The palatability of CGMP was acceptable and adherence was high. CGMP did not induce or change gastrointestinal symptoms. In conclusion, we found no immunomodulatory effects of CGMP in healthy adults. In a minor group of healthy adults, oral ingestion of 25 grams of CGMP during four weeks was safe, well tolerated, had acceptable palatability, and was without any effects on body weight.

Glycomacropeptide Safety and Its Effect on Gut Microbiota in Patients with Phenylketonuria: A Pilot Study

“…On the other hand, in humans, a 4-week randomized study conducted on twenty-four healthy subjects in 2021 has found no differences in fecal microbiota composition between adults consuming GMP or placebo. Similarly, no differences were found in body weight, fecal calprotectin, and SCFA levels at baseline and at week 4 between the two groups [29].…”

Potential Prebiotic Properties of Whey Protein and Glycomacropeptide in Gut Microbiome

“…Though GMP has growth-promoting effects on probiotic organisms in vitro and in animal models, these results are not consistently replicable in humans. Wernlund et al (2020) found that GMP supplementation in healthy human subjects had no effects on Shannon or observed diversity and no changes in microbiome composition or fecal SCFAs. Moreover, that study showed no effect of GMP on gastrointestinal symptoms.…”

Glycomacropeptide Protects against Inflammation and Oxidative Stress, and Promotes Wound Healing in an Atopic Dermatitis Model of Human Keratinocytes

“…Using animal models, GMP is reported as non-immunogenic [39]. It is also safe and well-tolerated by humans, with no immunomodulatory effects in healthy adults [40]. Nevertheless, there are no studies about the possible effects of GMP on keratinocytes, either orally or topically administered.…”