The Best and Worst Foods for IBS: A Dietitian’s Guide to Managing Flare-Ups

If you’ve recently been diagnosed with Irritable Bowel Syndrome (IBS) or have been living with unpredictable symptoms for years, you’re not alone. IBS affects an estimated 10–15% of the global population—and for many, diet plays a huge role in managing flare-ups.

In this guide, you’ll learn about the foods to avoid with IBS, the best foods for IBS, and how to shape an IBS flare-up diet that helps calm your digestive system and put you back in control of your gut health.

Why Food Matters So Much in IBS

IBS is a functional gastrointestinal disorder, meaning there's no visible damage to your digestive tract—but the way your gut behaves is out of sync. Symptoms can include:

Abdominal pain or cramping
Bloating and excess gas
Diarrhea, constipation, or both
A sense of incomplete bowel movements

While stress, hormones, and gut-brain communication also play a role, diet is one of the most direct and manageable factors that can trigger or soothe IBS symptoms.

Foods to Avoid with IBS: Common Triggers That Worsen Symptoms

High-FODMAP Foods

FODMAPs (Fermentable Oligo-, Di-, Mono-saccharides and Polyols) are certain types of carbohydrates that are poorly absorbed in the small intestine, ferment in the gut, and lead to gas, bloating, and discomfort.

Common high-FODMAP foods include:

Fruits: Apples, pears, watermelon, cherries, mangoes
Vegetables: Onions, garlic, cauliflower, broccoli, mushrooms
Dairy: Milk, soft cheeses, yogurt (due to lactose)
Grains: Wheat, rye, barley (especially in large quantities)
Legumes: Lentils, chickpeas, kidney beans
Sweeteners: Sorbitol, mannitol, xylitol (found in gum, mints, and “sugar-free” products)

Fatty and Fried Foods

Fat slows digestion and can overstimulate gut motility, especially in people with diarrhea-predominant IBS (IBS-D). These foods can cause bloating, cramping, and urgent bowel movements.

Foods to limit:

Fried foods (fries, fried chicken, battered fish)
High-fat meats (sausages, bacon, ribs)
Heavy cream sauces
Pizza and fast food

Caffeinated and Carbonated Beverages

Caffeine is a stimulant that can speed up gut transit time—bad news if you’re prone to diarrhea. Carbonated drinks introduce gas into the digestive tract, often worsening bloating.

Caution with:

Coffee and espresso drinks
Energy drinks
Cola and sodas
Sparkling water (if carbonation is an issue)

Alcohol

Alcohol can irritate the gut lining and disrupt the balance of gut bacteria. It also affects motility and can exacerbate both diarrhea and constipation.

Worst offenders:

Beer (due to carbonation and FODMAPs from wheat/barley)
Wine (especially sweet varieties)
Mixed drinks with soda or high-FODMAP juices

Best Foods for IBS: Gut-Friendly Options That Soothe Symptoms

Low-FODMAP Vegetables

These vegetables are gentler on the digestive system and less likely to cause gas:

Carrots
Zucchini
Spinach
Eggplant
Green beans
Lettuce

Lean Proteins

Protein tends to be well-tolerated by most people with IBS, especially when it’s lean and simply prepared.

Chicken (skinless)
Turkey
Eggs
Firm tofu
White fish (cod, tilapia)
Tempeh

Soluble Fibre-Rich Foods

Soluble fiber absorbs water and forms a gel-like substance in the gut, helping to regulate bowel movements—soothing both diarrhea and constipation.

Oats
Chia seeds
Psyllium husk (ideal for IBS-C and IBS-D)
Bananas (unripe)
Cooked carrots and squash

Lactose-Free Dairy and Alternatives

If you're lactose intolerant, even small amounts can be a trigger. Opt for:

Lactose-free milk
Almond, oat, or rice milk
Hard cheeses (cheddar, parmesan)
Plant-based yogurts with no added inulin or chicory root

Additional Tips for Managing IBS Through Diet

Keep a Food and Symptom DiaryTrack what you eat and how you feel. Patterns often emerge, helping you identify your personal triggers.
Eat Smaller, More Frequent MealsLarge meals can overwhelm the digestive system. Try 4–6 smaller meals per day to ease digestion.
Chew Slowly and Avoid Swallowing AirEating too quickly or talking while chewing can introduce excess air into your gut, causing bloating.
Watch for Hidden IngredientsPre-packaged foods may contain high-FODMAP ingredients like onion powder, high-fructose corn syrup, or inulin.
Consult a Registered DietitianA dietitian trained in IBS and FODMAP protocols can help you personalise your plan for better results.

At Nutrition and Co, we specialize in practical, evidence-based nutrition support for people just like you. Whether you’re newly diagnosed or still searching for answers, our expert dietitians are here to help you feel better, eat with confidence, and ditch the guesswork for good.

Don’t miss our free IBS Nutrition Guide, packed with dietitian-approved tips, food lists, and step-by-step strategies for managing flare-ups and improving your gut health.

Download the guide now and take the first step toward a calmer, happier gut.

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