Promote Gut Barrier Function with L-Glutamine† I’m sure you’ve heard about why gut barrier integrity is important. Your gut barrier is a crucial part of your whole body system, helping to “gatekeep” and manage what matter crosses over from your digestive tract into your bloodstream. Anyone who is invested in their gut health should be paying attention to L-Glutamine.† A Healthy Gut Is Key To Immune System Health† Glutamine supports and helps to maintain a healthy gut barrier. Your gut barriers are easily one of the most important parts of your immune system. It’s what keeps unwanted substances from entering your bloodstream where they can stimulate the body’s natural immune responses.