A diverticulitis flare up occurs when small pouches in the colon, known as diverticula, become inflamed or infected, causing pain, fever, and digestive distress. During this time, the primary goal of your diet is to reduce irritation and give your digestive system a break. A multi-stage dietary approach is typically recommended, starting with liquids and slowly adding low-fiber foods before eventually transitioning back to a high-fiber, long-term maintenance plan. Always consult with a healthcare provider or a registered dietitian before starting a new diet for diverticulitis.
The Initial Clear Liquid Diet
For a severe flare up, a doctor may recommend starting with a clear liquid diet for a few days to minimize stress on your digestive tract. This diet provides hydration and some nutrients without creating solid waste that can further irritate the inflamed diverticula.
Foods and liquids allowed during this phase include:
- Clear broths
- Pulp-free juices
- Water
- Tea or coffee (without milk or cream)
- Gelatin (without fruit pieces)
- Ice pops (made from clear juice)
- Clear sports drinks
This is a temporary diet and should only be followed for the duration recommended by your doctor.
Transitioning to a Low-Fiber Diet
As your symptoms improve, you can begin to introduce low-fiber foods. This diet consists of easily digestible foods that don't add significant bulk to your stool. Good options for this phase include:
Grains
- White bread and crackers
- White rice
- Plain white pasta
Fruits (peeled, cooked, or canned)
- Applesauce
- Bananas
- Canned peaches and pears
Vegetables (peeled, cooked, or canned)
- Mashed potatoes (without skin)
- Peeled, well-cooked carrots
Proteins
- Eggs
- Tofu
- Skinless, lean poultry or fish
Dairy (if tolerated)
- Milk
- Cottage cheese and soft cheeses
Reintroducing Fiber for Long-Term Prevention
After your flare up has fully resolved, typically within a week or two, you should gradually reintroduce a high-fiber diet. A high-fiber diet is crucial for long-term management and prevention of future diverticulitis attacks by promoting regular bowel movements and reducing pressure on the colon. Start slowly to avoid discomfort.
Comparing Flare-Up and Prevention Diets
| Food Category | During a Flare-Up (Low-Fiber) | For Prevention (High-Fiber) |
|---|---|---|
| Grains | White bread, white rice, low-fiber cereals | Whole-wheat bread, brown rice, oats, quinoa |
| Fruits | Applesauce, canned fruits, bananas, pulp-free juice | Whole fruits with skin (apples, pears, berries) |
| Vegetables | Peeled, well-cooked, or canned vegetables | Raw vegetables, leafy greens, broccoli, carrots |
| Protein | Eggs, lean poultry, fish, smooth nut butter | Lean protein, beans, legumes, nuts, seeds |
| Dairy | Milk, yogurt, cottage cheese (if tolerated) | Same, plus options with seeds or fruit (if tolerated) |
Foods to Avoid During a Flare-Up
Certain foods can worsen symptoms during an acute flare up. These include:
- High-fiber foods
- Spicy foods
- Fried or greasy foods
- Processed meats
- Alcohol
- Foods high in refined sugar
The Evolving Advice on Nuts and Seeds
While older advice recommended avoiding nuts, seeds, and popcorn, recent research does not support this. They are now considered part of a healthy, high-fiber diet for prevention once a flare-up has subsided. During an active flare, stick to low-fiber options.
Hydration and When to Seek Medical Attention
Staying well-hydrated is critical throughout all stages, especially during a clear liquid diet. Drink plenty of water.
Contact your doctor if your symptoms do not improve after a few days on the clear liquid diet, or if they worsen. Severe abdominal pain, fever, nausea, and vomiting require immediate medical attention.
Conclusion
Managing a diverticulitis flare up involves a strategic, phased dietary approach. By starting with clear liquids, progressing to low-fiber foods, and eventually reintroducing a fiber-rich diet, you can support healing and help prevent future attacks. While older advice about nuts and seeds is now outdated, always listen to your body and consult with your healthcare team to find the right diet for your specific needs. Understanding what foods are good for a diverticulitis flare up is a key part of effectively managing this condition.
For more information on digestive health, you can visit the National Institute of Diabetes and Digestive and Kidney Diseases.
