What you eat with ulcerative colitis depends largely on whether your disease is flaring or in remission. During a flare, the goal is to minimize irritation by eating soft, low-fiber foods that are easy to digest. In remission, you can gradually reintroduce fiber and a wider variety of foods that help keep inflammation in check and prevent nutrient gaps.
Eating During a Flare
When your colon is actively inflamed, raw vegetables, whole grains, nuts, and seeds can scrape against damaged tissue and make symptoms worse. A low-fiber approach keeps food moving through your gut with as little friction as possible. The specific foods that work well during flares include white rice, regular pasta, and baked goods made from refined flour like white bread, saltines, and pancakes. Hot or cold cereals with less than 2 grams of fiber per serving, especially rice-based cereals, are also gentle options.
For protein, lean choices like tender chicken, turkey, fish, shellfish, eggs, tofu, and creamy peanut butter are all well tolerated. Vegetables aren’t off-limits, but they need to be thoroughly cooked until very soft. Canned or well-cooked carrots, potatoes, and green beans, along with plain tomato sauce, are reliable choices. The best cooking methods during a flare are simmering, steaming, poaching, stewing, and braising. Baking or microwaving in a covered dish works too. The key is getting everything to a tender texture before you eat it.
The IBD Anti-Inflammatory Diet, developed at UMass, formalizes this into phases. During Phase 1 (active flare), all foods should be cooked, pureed, ground, or finely minced with no seeds, stems, or hard peels. Think avocados, bananas, pureed carrots and spinach, ground chicken or turkey, and nut butters. Phase 2, for intermittent symptoms, loosens things up to soft-textured foods: peeled apples, riced cauliflower, blueberries (pureed to remove seeds), tofu, and minced proteins.
Eating During Remission
Once symptoms settle, your diet can and should expand. This is when fiber becomes your ally rather than your enemy. Fiber feeds beneficial gut bacteria, which produce short-chain fatty acids that help maintain the colon’s protective lining. The recommended daily intake for adults is 25 to 38 grams, though most people with UC do best building up slowly rather than jumping to that target.
Soluble fiber is the priority. It dissolves in water and forms a gel-like substance in the colon, which is gentler on inflamed tissue than insoluble fiber. Good sources include oats, barley, bananas, cooked carrots and other root vegetables, peas, beans, and psyllium husk (which is roughly 70% soluble fiber). Pectin, found naturally in apples and citrus fruits, is another soluble fiber that gut bacteria digest almost completely.
Insoluble fiber, the kind found in whole grain skins, raw vegetables, nuts, and fruit peels, adds bulk to stool and is harder to ferment. It’s not forbidden in remission, but it’s worth introducing cautiously. Phase 3 of the IBD Anti-Inflammatory Diet reflects this: broccoli, cabbage (including fermented varieties like sauerkraut), whole nuts and seeds, citrus fruits, and dried fruits all become options as tolerated.
Omega-3 Fats and Inflammation
Omega-3 fatty acids directly compete with the compounds your body uses to produce inflammatory signals. They serve as raw material for molecules called resolvins and protectins that actively help resolve inflammation. They also reduce oxidative stress and lower production of several inflammatory proteins in the gut lining. The practical translation: eating omega-3-rich foods regularly may help keep intestinal inflammation quieter.
The best food sources are fatty fish (salmon, mackerel, sardines, herring), walnuts, and flaxseed. Two servings of fatty fish per week is a reasonable baseline for the general population, and olive oil is another useful source of anti-inflammatory fats for cooking and dressings.
Probiotics Worth Knowing About
Most probiotic products have little evidence behind them for UC specifically, but two formulations stand out. One is a nonpathogenic strain called E. coli Nissle 1917 (sold as Mutaflor), which performed as well as the standard UC medication mesalamine for both inducing and maintaining remission over a full year in several large clinical trials. The other is VSL#3, a combination of eight bacterial strains that achieved similar remission rates to mesalamine in shorter studies of up to 24 weeks.
These aren’t substitutes for medical treatment, but they’re the only probiotics with meaningful clinical trial data in UC. General yogurt or kefir consumption may support overall gut health, but the evidence is far less specific.
The Dairy Question
Many people with UC assume they need to cut dairy entirely. The reality is more nuanced. In a study of UC patients, only about 9% actually had lactose malabsorption, which is not dramatically higher than the general population. A small number of patients did develop temporary lactose issues during flares that resolved when the flare settled. If dairy doesn’t cause you symptoms, there’s no clinical reason to avoid it. Milk, yogurt, and cheese provide calcium and protein that are valuable when your body is under inflammatory stress. If you’re unsure, try small amounts of yogurt or aged cheese first, since these contain less lactose than milk.
Nutrient Gaps to Watch For
Chronic inflammation and reduced food intake during flares create real risks for nutritional deficiencies. Vitamin D deficiency or insufficiency affects 37% to 51% of people with inflammatory bowel disease, depending on factors like sun exposure, diet, and disease severity. Iron-deficiency anemia is another common problem, since blood loss from the inflamed colon drains iron stores. Low vitamin D, low albumin (a protein made by the liver), and iron-deficiency anemia are all markers that clinicians associate with a more aggressive disease course.
Practical steps include eating iron-rich foods like lean red meat, shellfish, spinach, and fortified cereals when tolerated. For vitamin D, fatty fish pulls double duty here alongside egg yolks and fortified dairy or plant milks. If you’ve been in a prolonged flare or have been eating a very restricted diet, blood work to check these levels is worthwhile.
Staying Hydrated During Diarrhea
Frequent diarrhea during flares pulls water and electrolytes out of your body faster than plain water can replace them. The American Gastroenterological Association recommends a simple oral rehydration solution you can make at home: half a level teaspoon of salt dissolved in one liter of drinking water, with a small amount of sugar to help your intestines absorb the fluid. Coconut water, broth, and diluted fruit juices also help replenish sodium and potassium. Sipping small amounts steadily through the day works better than drinking large volumes at once, which can trigger more bowel urgency.
Putting It All Together
The simplest framework is to think in terms of texture and fiber. During flares, eat soft, low-fiber, well-cooked foods. As symptoms improve, gradually add soluble fiber sources like oats, bananas, and cooked root vegetables. In full remission, broaden your diet to include whole grains, raw fruits and vegetables, nuts, and seeds, paying attention to how each food affects you individually. Throughout all phases, prioritize fatty fish and olive oil for their anti-inflammatory benefits, keep up with fluids and electrolytes during diarrhea, and be aware that iron and vitamin D are the nutrients most likely to fall short over time.