What should I know about leaky gut glutamin?

The question about glutamine for 'leaky gut' is common, but the evidence is mixed. Glutamine is a key fuel for intestinal cells and may support tight junction integrity, which is relevant for gut barrier function. Some small human studies and animal models suggest glutamine supplementation can reduce intestinal permeability, especially in conditions like chemotherapy or critical illness. However, large, high-quality randomized controlled trials in otherwise healthy individuals with 'leaky gut' symptoms (bloating, food sensitivities, fatigue) are lacking. The concept of 'leaky gut' as a clinical diagnosis is controversial; many mainstream gastroenterologists do not recognize it as a distinct disease. Excessive glutamine intake (>30 g/day) can cause nausea, abdominal discomfort, or elevated ammonia. My advice: focus on a whole-food diet rich in protein, fiber, and fermented foods first. If you suspect increased intestinal permeability, consult a physician for proper testing (e.g., lactulose-mannitol test). Glutamine is not a proven cure-all; the evidence is mostly mechanistic and insufficient for a strong recommendation.