Ulcerative colitis (UC) is a chronic inflammatory bowel disease that causes inflammation and ulcers in the innermost lining of the colon and rectum, leading to abdominal pain, diarrhea, urgency, and rectal bleeding. Unlike many of the conditions on this site, UC genuinely has two different nutritional pictures rather than one: what helps during an active flare is often the opposite of what helps you stay in remission, which is why this grocery list is organized around that distinction rather than a single fixed food list.
It is worth being upfront that, according to a multicenter randomized clinical trial, the European Society for Clinical Nutrition and Metabolism (ESPEN) guidelines state there is insufficient evidence for any single specific dietary approach in people with active UC. The same research notes that vegetable- and fiber-rich diets are associated with a lower risk of developing UC in the first place, while diets high in omega-6 fatty acids, red meat, refined sugar, and fast food are associated with a higher risk, which is a meaningfully different question from what to eat once you already have an active flare. This grocery list reflects that distinction: lower-fiber, easier-to-digest foods during flares, and a more fiber-rich, Mediterranean-style pattern once you are in remission.
How Diet Affects Ulcerative Colitis: Flares vs. Remission
Fiber plays two opposite roles depending on disease activity. During a flare, insoluble fiber from raw vegetables and fruit skins can mechanically irritate an already inflamed colon. During remission, that same fiber feeds the beneficial gut bacteria that produce protective short-chain fatty acids, which is why fiber recommendations flip almost entirely between the two states.
An anti-inflammatory eating pattern can reduce inflammation even without symptoms. A six-month randomized, placebo-controlled trial found that UC patients in clinical remission who followed an anti-inflammatory diet, emphasizing fiber, probiotics, antioxidants, and omega-3 fatty acids while reducing red meat, processed meat, and added sugar, were significantly more likely to show a meaningful reduction in fecal calprotectin, a marker of subclinical gut inflammation, than those following standard dietary guidance.
The Mediterranean diet is one of the better-supported patterns for UC, though mainly for remission. A review of nutrition and supplementation in UC notes that ESPEN recommends the Mediterranean diet as an optional dietary approach for UC patients, built around vegetables, fruits, legumes, whole grains, nuts, fish, and olive oil, with reduced red meat in favor of leaner alternatives like poultry.
Omega-3 evidence is genuinely mixed. A nutrition review covering UC supplementation found that omega-3 supplementation in patients already in remission reduced relapse rates at two and three months into one study, but that this benefit was not sustained by the end of the full study period compared with the control group, which is why omega-3-rich foods are worth including but not relied on alone.
Blood loss from inflammation can lead to iron-deficiency anemia. WebMD’s guidance on managing UC through diet notes that ongoing low-level bleeding from the colon’s lining can cause iron-deficiency anemia and fatigue, making iron-rich foods a meaningful part of a UC diet regardless of whether you are in a flare or remission.
Ulcerative Colitis Diet Foods List: What to Buy
During a Flare: Low-Fiber, Easy-to-Digest Foods (Most Important Category)
These foods are gentle on an actively inflamed colon and are typically the easiest to tolerate when symptoms are at their worst.
Best choices:
- Skinless chicken breast and turkey, shredded or ground (easy to digest, minimal residue)
- White fish such as cod or tilapia
- Eggs
- White rice, rice cakes, and white pasta (low in fiber, gentle on an inflamed gut)
- Peeled, cooked root vegetables such as potatoes, sweet potatoes, and carrots
- Cooked, peeled fruit without skin or seeds, such as ripe banana, melon, and peeled apple or pear
- Smooth nut butters, in small amounts, rather than whole nuts
During Remission: Fiber-Rich, Anti-Inflammatory Foods
Once symptoms have settled, gradually reintroducing fiber and emphasizing the foods linked to lower inflammation becomes the priority.
Best choices:
- Oats and whole grains, introduced gradually
- Legumes such as lentils and beans, introduced gradually as tolerance allows
- A wide variety of vegetables, cooked until soft initially and progressing toward raw as tolerated
- Whole fruit with skin, as tolerance allows
- Extra virgin olive oil as your primary added fat
Iron-Rich Foods to Address Anemia
Best sources:
- Lean red meat and poultry, in moderate portions
- Seafood
- Spinach, cooked until soft (better tolerated than raw during sensitive periods)
- Fortified breakfast cereals
- Egg yolks
- Artichokes, well cooked
Omega-3 Rich Foods
Best sources:
- Salmon and mackerel
- Sardines
- Walnuts, once tolerated
- Ground flaxseed, once tolerated
Low-Fat Dairy and Alternatives
Lactose intolerance is common alongside IBD, so low-fat and lactose-free options are often better tolerated than full-fat dairy.
Best choices:
- Low-fat or skim milk, or lactose-free milk if you notice intolerance
- Low-fat plain yogurt, particularly varieties with live probiotic cultures
- Fresh, mild cheeses such as cottage cheese
Healthy Fats from the Mediterranean Pattern
- Extra virgin olive oil
- Avocado, in moderation and as tolerated
- A small handful of nuts and seeds, once you have moved past an active flare
Foods to Avoid With Ulcerative Colitis
Insoluble Fiber and Raw Cruciferous Vegetables During a Flare
The Crohn’s and Colitis Foundation’s guidance specifically recommends avoiding insoluble fibers, found in raw cruciferous vegetables and the skins and peels of fruit, particularly during a flare, since these can mechanically irritate the inflamed lining of the colon.
Foods to avoid during a flare:
- Raw broccoli, cabbage, Brussels sprouts, and cauliflower
- Fruit and vegetable skins and peels
- Whole nuts and seeds
- Popcorn
Red and Processed Meat
Higher intake of red and processed meat has been associated with increased risk and worsened disease activity in UC research, making this one of the more consistent dietary recommendations across both flares and remission.
Foods to limit:
- Bacon, sausage, and deli meats
- Frequent red meat consumption, even outside of active flares
Added Sugar and Ultra-Processed Foods
Foods to limit:
- Sugary cereals, pastries, and candy
- Packaged snack foods and fast food
- Sugar-sweetened beverages
Alcohol and Caffeine
Foods and beverages to limit, especially during flares:
- Alcohol of all kinds
- Coffee and other caffeinated beverages, particularly if you notice they worsen urgency or diarrhea
High-Fat and Fried Foods
Foods to avoid, particularly during a flare:
- Fried foods
- Heavy cream sauces and gravies
- Fatty cuts of meat
Dairy, If You Notice Lactose Intolerance
Foods to limit if applicable:
- Regular milk
- Ice cream
- Soft, fresh cheeses, if you notice symptoms after eating them
Ulcerative Colitis Diet Grocery List by Store Section
This list covers one week for one adult, with notes on which items are flare-friendly versus better suited to remission.
Produce
- Potatoes and sweet potatoes, flare-friendly when peeled and cooked (4 medium)
- Carrots, peeled and cooked during flares, raw as tolerated in remission (500g)
- Ripe bananas, flare-friendly (1 bunch)
- Melon, flare-friendly (1 small)
- Apples and pears, peeled during flares, whole with skin once in remission (4 each)
- Spinach, cooked soft for iron (1 bag)
- A variety of seasonal vegetables for remission weeks, gradually increased in raw form as tolerated (2 to 3 types)
Meat, Seafood, and Eggs
- Skinless chicken breast and turkey (600g combined)
- Fresh salmon and mackerel (2 to 3 portions)
- White fish such as cod (2 portions)
- Eggs (1 dozen)
- Lean red meat, in moderate amounts and limited frequency (300g)
Dairy and Alternatives
- Low-fat or lactose-free milk (1 carton)
- Low-fat plain yogurt with live cultures (1 tub)
- Cottage cheese (1 small tub)
Grains and Pantry
- White rice and rice cakes, flare-friendly (1 kg combined)
- White pasta, flare-friendly (1 box)
- Oats and whole grains for remission weeks (1 container)
- Lentils and beans for remission weeks (2 to 3 cans)
- Smooth nut butter (1 jar)
- Olive oil (1 bottle)
- Ground flaxseed for remission weeks (1 small bag)
Frozen
- Frozen white fish fillets (1 bag)
- Frozen peeled fruit, such as mango or banana, for smoothies (1 bag)
- Frozen spinach (1 bag)
Beverages
- Water, primary beverage
- Oral rehydration solution or electrolyte drinks, during flares with diarrhea
- Alcohol and caffeine, limited
Practical Tips for Managing Ulcerative Colitis Through Diet
Keep separate flare and remission food lists rather than one fixed diet. Because fiber and raw produce tolerance shift so dramatically between active disease and remission, the single most useful habit is adjusting your grocery list to match your current state rather than picking one diet and sticking to it year-round.
Eat smaller, more frequent meals during a flare. Five or six smaller meals tend to be easier to tolerate than three large ones when your gut is inflamed and sensitive.
Cook vegetables until soft and remove skins, seeds, and pulp during flares. Pureeing or thoroughly cooking produce reduces the mechanical irritation that raw, fibrous foods can cause to an inflamed colon.
Prioritize iron-rich foods if you have ongoing bleeding. Chronic blood loss from active UC is a common cause of fatigue, so working iron-rich foods into your diet consistently, alongside any iron supplementation your doctor recommends, can meaningfully improve energy levels.
Reintroduce fiber gradually once you reach remission. Moving too quickly from a low-fiber flare diet back to raw vegetables and whole grains can trigger symptoms, so add fiber back in small increments over several weeks.
Stay ahead of dehydration during diarrhea flares. Water alone may not replace lost electrolytes quickly enough during a significant flare, so oral rehydration solutions can be a useful addition.
Work with a gastroenterologist or registered dietitian, especially during flares. Because UC carries a real risk of malnutrition during active disease, professional guidance helps you avoid restricting too much for too long while you manage symptoms.
The Bottom Line
Ulcerative colitis genuinely calls for two different approaches to food: gentle, low-fiber, easy-to-digest meals during an active flare, and a more fiber-rich, Mediterranean-style, anti-inflammatory pattern once you reach remission. Build your flare-week grocery list around peeled root vegetables, cooked fruit, white rice, and lean proteins, then gradually shift toward whole grains, legumes, raw produce, and omega-3-rich fish as symptoms settle, while keeping red and processed meat, added sugar, alcohol, and fried foods limited throughout. Because the research consensus is that no single diet works for everyone with UC, matching your grocery list to your current disease activity, and working with your care team along the way, matters more than following any list rigidly.
Disclaimer: Nutritional data referenced in this article is sourced from USDA FoodData Central. This article is for informational purposes only and does not constitute medical or dietary advice. Ulcerative colitis is a chronic condition that typically requires ongoing medical management, and diet should be used alongside, not instead of, treatment prescribed by your gastroenterologist. Always consult your doctor or a registered dietitian before making significant dietary changes, particularly during an active flare, since unsupervised restrictive eating can lead to malnutrition.
