1. You Have a Food Intolerance
Poor absorption of fructose is thought to be one of the dietary triggers for irritable bowel syndrome and could be the reason why tomatoes give you diarrhea.
But keep in mind that a little tomato here and there may be fine. “Small amounts of tomatoes may not cause a problem, but where some people get tripped up is with canned tomatoes or tomato-based products like ketchup and pasta sauce,” says Kristin West, RD. “These other products tend to have additives like high-fructose corn syrup or garlic, and that can take you into the high-FODMAP zone.”
So if you were wondering why tomato sauce gives you diarrhea or hurts your stomach, these ingredients could be to blame. Tomato soups and juices can also contain additives that may not agree with your stomach, so be sure to read the labels.
Fix it: If symptoms become problematic, it’s best to have your doctor or a dietitian help you plan a diet around your restrictions so you can avoid an upset stomach and diarrhea after eating tomatoes.
