I didn't get a kit for the urine sample for leaky gut in my Gut Health Test kit, did I receive the right kit? If you ordered a Gut Health Test that includes leaky gut, we'll test for it using stool, not urine. We test for leaky gut through your stool sample, so there is no need for a urine sample. The leaky gut biomarker we look for in the stool is called zonulin. Read our complete guide to leaky gut testing