Which Foods Are Often Triggers for UC Flares?

Arielle Leben M.S., R.D., C.D.N., a nutrition specialist at the Inflammatory Bowel Disease Center at NYU Langone Health in New York City, offers advice on foods to skip if you're worried about a flare with ulcerative colitis.

In general, the foods that aggravate ulcerative colitis are those that are linked with symptoms such as gas, bloating, abdominal pain, accelerated transit time, or diarrhea. For example, if you were to have a huge salad with a lot of leafy greens, raw vegetables, nuts, seeds, you would be eating a lot of something called insoluble fiber, which is the other type of fiber.

This is the type of fiber that promotes the movement of food through the digestive tract and helps to accelerate bowel movements. Not what you really want when you're flaring. Think of it like a broomstick that sweeps things along in an undigested way and can be very irritating.

High-fat meals, like greasy fried foods and very large meals, also can be a stimulant and triggering, because they tend to stimulate something called the gastrocolic reflex more strongly. This is a reflex that controls motility of intestinal contents through the digestive tract, which can actually aggravate diarrhea.

Lastly, another potential aggravator of symptoms can be high FODMAP foods or things such as sugar alcohols, sorbitol, mannitol, xylitol those are just some of the names. They're always listed on the ingredient label and those tend to make gas and bloating worse, and often times accelerate diarrhea as well.