Zinc carnosine works with bovine colostrum in truncating heavy exercise-induced increase in gut permeability in healthy volunteers.
Level 2 - randomized trial
Double-blind, placebo-controlled crossover randomized trial with supporting in vitro experiments
PubMed 27357095 · doi:10.3945/ajcn.116.134403
What was done
Eight healthy volunteers completed a 4-arm, double-blind, placebo-controlled crossover trial comparing 14 days of placebo, zinc carnosine (ZnC), bovine colostrum, or ZnC plus bovine colostrum. Standardized exercise sessions were performed on day 2 and day 14 of each treatment arm. Gut permeability was assessed by 5-hour urinary lactulose:rhamnose ratios. In vitro experiments in Caco-2 and HT29 intestinal cell lines evaluated epithelial resistance, apoptosis markers, and tight junction protein phosphorylation under a 2°C temperature elevation.
What was found
Heavy exercise increased body temperature by 2°C and increased gut permeability 3-fold (lactulose:rhamnose ratio rose from 0.32 ± 0.016 baseline to 1.0 ± 0.017 at 14 days with placebo; P < 0.01). ZnC alone or colostrum alone blunted this permeability rise by 70% at 14 days. The combination regimen showed an earlier effect, reducing the permeability increase by 30% by day 2 (P < 0.01). In vitro, a 2°C temperature increase doubled apoptosis and decreased epithelial resistance 3- to 4-fold; ZnC or colostrum reduced these effects by 35%–50%, with maximal benefit from the combination (all P < 0.01).
Why it matters
Supplementation with zinc carnosine and bovine colostrum may protect gut barrier function against hyperthermia and strenuous exercise, offering a targeted strategy for athletes and military personnel.
Limits
The human trial included a very small sample size (n = 8). The abstract does not specify participant sex or baseline fitness, nor does it measure clinical endpoints like heat stroke incidence or gastrointestinal symptoms in vivo. Much of the mechanistic pathway evidence relies on cell culture models.