Brief Answer: many causes Detailed Answer: there are many causes of watery diarrhea, however helicobacter pylori is not a cause of diarrhea. The fact that it has been going on for a year is concerning, however if you had a normal colonoscopy and normal stool tests that is good news. Other testing that must be considered: blood test for thyroid disease, for celiac sprue (gluten intolerance), fat in stool (due to malabsorption), pancreatic diseases can cause diarrhea as well. If all testing is negative, you may have Irritable bowel syndrome, and different medications can be tried to control your diarrhea, usually by trial and error until finding the adequate medication. If your husband has it too, maybe it is something in the diet? you would need to talk to a nutritionist to go over every shared meal ingredients. Hope that helps, let me know if you have further questions or concerns.

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