“Leaky gut” is a popular term; medically, “increased intestinal permeability” is more accurate. Key point: it is typically a mechanism seen in certain conditions and exposures, not a stand-alone diagnosis with a one-size-fits-all cure. Factors that can stress the barrier include heavy alcohol use, chronic stress, poor sleep, ultra-processed diets, certain medications, and active inflammation. Practical support focuses on fundamentals: increase fiber diversity to a tolerated level, ensure adequate protein, build an anti-inflammatory eating pattern (often including omega-3-rich foods), reduce alcohol/added sugar load, and improve sleep/stress regulation. Fermented foods or goal-matched probiotic/postbiotic protocols may help symptoms for some, but universal supplement claims are not evidence-based. If you have persistent diarrhea, bleeding, weight loss, or nighttime symptoms, seek medical evaluation. Avoid marketing-driven “permeability cures”; prioritize measurable symptom targets and a medically grounded plan.