Work With Your IBD Team
Ulcerative colitis is a serious condition requiring proper medical management. Diet can help manage symptoms but doesn't replace medication. Work with your gastroenterologist and an IBD-specialist dietitian to create a personalised nutrition plan alongside your treatment.
Ulcerative colitis is an inflammatory bowel disease (IBD) causing inflammation and ulcers in the colon's inner lining. Unlike IBS (a functional disorder), UC involves actual damage to the gut tissue and requires medical treatment.
There's no single "UC diet" that works for everyone. However, research has identified patterns that help many people reduce flare frequency, manage symptoms during active disease, and maintain remission.
Flares vs Remission: Different Needs
Your dietary approach should shift based on disease activity:
During Flares (Active Disease)
When your colon is inflamed, the goal is to reduce irritation and give your gut time to heal. This often means temporarily restricting fibre, particularly insoluble fibre that can scrape against inflamed tissue.
Focus on: Low-residue foods, well-cooked vegetables, lean proteins, white rice/bread, avoiding raw foods.
During Remission
When inflammation is controlled, you can (and should) gradually reintroduce more variety. Fibre becomes beneficial again, supporting gut bacteria and overall health.
Focus on: Gradually increasing fibre diversity, Mediterranean-style eating, prebiotic foods, omega-3 fatty acids.
Common Trigger Foods
Research and patient surveys consistently identify certain foods as problematic for many (not all) UC patients:
Often Problematic
- High-fat fried foods
- Spicy foods
- Raw vegetables (during flares)
- Nuts and seeds (during flares)
- Popcorn
- Caffeine and alcohol
- Fizzy drinks
- Dairy (if lactose intolerant)
- High-FODMAP foods
- Processed/ultra-processed foods
Generally Well-Tolerated
- White rice and pasta
- Well-cooked vegetables
- Lean proteins (chicken, fish, eggs)
- Bananas and melons
- Oats (often well-tolerated)
- Smooth nut butters
- Avocado
- Salmon and oily fish
- Bone broth
- Probiotic foods (yoghurt, kefir)
Individual Variation
These lists are starting points, not rules. Some people with UC tolerate salads perfectly; others can't touch raw vegetables. Keep a food diary during flares to identify YOUR specific triggers. What bothers someone else may be fine for you.
Evidence-Based Dietary Approaches
Mediterranean Diet
The most studied dietary pattern for IBD. Rich in omega-3s, polyphenols, and fibre diversity, it's associated with reduced inflammation and longer remission periods. Best adopted during remission rather than active flares.
Specific Carbohydrate Diet (SCD)
Eliminates complex carbohydrates and most grains. Some studies show benefit for UC patients, though evidence is mixed. Very restrictive and requires careful planning to avoid nutritional deficiencies.
Low FODMAP
Originally developed for IBS, but many UC patients have overlapping IBS-like symptoms. A low FODMAP approach during flares can reduce bloating and urgency, though it should be temporary.
IBD-AID (Anti-Inflammatory Diet)
Developed at UMass, this combines elements of SCD with prebiotics and probiotics. Early research is promising but limited. Phases from restrictive to more liberal as symptoms improve.
Key Nutrients to Watch
UC increases risk of certain deficiencies, particularly during active disease or if you've had surgery:
- Iron - Blood loss from inflamed gut can cause anaemia. Get levels checked regularly.
- Vitamin D - Many UC patients are deficient. Important for immune function and bone health. Supplementation often needed.
- Vitamin B12 - Can be low if you've had terminal ileum involvement or surgery.
- Calcium - Important if avoiding dairy or using corticosteroids long-term.
- Zinc - Often depleted during flares. Supports gut healing.
- Omega-3 fatty acids - Anti-inflammatory. Oily fish twice weekly or supplementation may help.
Practical Tips
- Eat smaller, more frequent meals - Large meals can overwhelm an inflamed gut
- Stay hydrated - Especially important if experiencing diarrhea
- Cook vegetables well - Easier to digest than raw, especially during flares
- Chew thoroughly - Start digestion in the mouth to reduce gut workload
- Keep a food and symptom diary - Pattern recognition is key
- Don't eliminate foods unnecessarily - Only remove what actually causes problems
- Plan ahead - Know where toilets are, carry safe snacks when out
The Gut Microbiome Connection
UC is associated with reduced microbiome diversity. During remission, eating a wide variety of plant foods (the "30 plants per week" concept) may help restore diversity and support longer remission.
Prebiotic foods (garlic, onion, leeks, bananas, oats) feed beneficial bacteria - but introduce slowly as some can initially cause gas.
Key Takeaway
There's no universal UC diet. Your approach should flex with disease activity - more restrictive during flares, more varied during remission. Work with an IBD dietitian to identify your personal triggers and ensure nutritional adequacy. Diet is part of your toolkit, alongside medication and medical monitoring.
References
- Crohn's & Colitis UK. (2024). Food and IBD.
- Levine, A. et al. (2020). Dietary Guidance From the International Organization for the Study of IBD. Clinical Gastroenterology & Hepatology
- Durchschein, F. et al. (2016). Diet therapy for IBD. World Journal of Gastroenterology
- Sigall-Boneh, R. et al. (2021). Research gaps in diet and nutrition in IBD. Journal of Crohn's and Colitis
- Lewis, J.D. et al. (2021). A Randomized Trial Comparing the SCD to a Mediterranean Diet in Adults With Crohn's Disease. Gastroenterology
