What you've heard: A "leaky gut" is behind your symptoms
Is leaky gut real?
Real in specific diseases, unproven as an everyday diagnosis. Evidence grade: Emerging.
Published Updated
The "What you've heard" box in Chapter 6
Real in specific diseases, unproven as an everyday diagnosis
The evidence
How easily things slip through the gut lining can be measured, and that leakiness does rise in celiac disease and inflammatory bowel disease, and with endurance exercise, pregnancy and anti-inflammatory painkillers. As sold online, though, "leaky gut" is a diagnosis without a reliable test: one widely used commercial blood kit for zonulin, a protein that helps regulate the seal between gut cells, does not detect zonulin.11
Where the book tests it
Related claims
- Is raw milk healthier or safe?Against, and the risk is measured.Evidence grade: Probable. Good observational evidence with a plausible mechanism, or small or few trials.
- Do probiotic pills fix your gut?For healthy people, unsupported; spend the money on yogurt and beans.Evidence grade: Probable. Good observational evidence with a plausible mechanism, or small or few trials.
- Can a greens powder replace vegetables?Expensive vitamins, and no substitute for vegetables.Evidence grade: Emerging. Early, small, animal-only, or actively contested.
Sources
The "What you've heard" box in Chapter 6
- 11.Camilleri, M. (2019). "Leaky gut: mechanisms, measurement and clinical implications in humans." Gut, 68(8), 1516-1526. https://doi.org/10.1136/gutjnl-2019-318427 ; Scheffler, L., Crane, A., Heyne, H., Tönjes, A., et al. (2018). "Widely used commercial ELISA does not detect precursor of haptoglobin2, but recognizes properdin as a potential second member of the zonulin family." Frontiers in Endocrinology, 9, 22. https://doi.org/10.3389/fendo.2018.00022
Note numbers are those of Chapter 6, The Gut That Expects Dirt.
This verdict is one of the "What you've heard" boxes in Chapter 6, The Gut That Expects Dirt, where the book tests the claims people repeat against the studies behind them. The grade rates the evidence behind the verdict, by the book's stated method.
Educational content, not medical advice. Disclaimer.