IBS trigger foods: What to avoid in a flare up

IBS trigger foods
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A diagnosis of IBS can be challenging. You’ll likely experience flare-ups of symptoms like constipation, gas, bloating, and diarrhea – this happens when your gut has an exaggerated response to foods it struggles to digest. At first, the symptoms may seem unpredictable, and you’ll likely feel anxious about mealtimes. That’s why learning about your IBS trigger foods can empower you to choose food that makes you feel good while minimizing unpleasant symptoms. 

But remember: no one size fits all. Another person’s IBS trigger foods might be different from yours – it takes trial and error to identify what works and what doesn’t. 

Yet there are common IBS trigger foods that cause problems for many. Focusing on your body’s responses to these foods and keeping a food diary can pinpoint which foods you can tolerate and which cause flare-ups.

We’ll take a closer look at common IBS trigger foods as a starting point to investigate your personal symptoms. We’ll also cover what you can eat to better manage your symptoms and enjoy mealtimes again. 

What are common IBS trigger foods?

Insoluble fiber

There are trigger foods known to stimulate the gut, including dietary fiber,” says Dr. Shyamala Vishnumohan, Doctor of Food and Nutrition Science (Ph.D.), Certified Prenatal Dietitian, and Real Food Advocate. “These include: fruits, vegetables, whole grains, legumes, nuts, and seeds. You may experience discomfort if you’re prone to IBS symptoms like diarrhea.”

Yet fiber is essential for gut health, so don’t cut it out entirely. The trick is to minimize fiber that your body finds difficult to digest. According to the CDC, there are two types of fiber — soluble fiber, which dissolves in water, and insoluble fiber, which doesn’t. Insoluble fiber can often trigger IBS flare-ups due to excess fluid in the gut. 

So, how do you tell the difference? Examples of insoluble fiber include specific fruits and vegetables, such as parsnips, potatoes, and celery. You can also find it in grains like barley, wheat, and rye. It’s worth monitoring which sources of fiber you can 

Beans and legumes

Beans and legumes are brilliant sources of protein and fiber, but they are common IBS trigger foods. This is because they contain oligosaccharides. 

Dr. Vishnumohan explains: “[They] tend to receive a wonderful reception from our hungry resident gut bacteria, resulting in rapid fermentation. Fermentation is really a good thing — it helps produce beneficial Short-Chain Fatty Acids and is key to bowel health. Yet fermentation can produce excessive gas, which causes the intestine to stretch and triggers pain signals in people with IBS.” 

Try soaking beans overnight before cooking to aid digestion while allowing you to reap the health benefits. 

bowl of bean chili with sour cream

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Dairy products are common IBS trigger foods. This is because they contain lactose which is difficult for the gut to digest. Think lactose from dairy products like milk, soft cheese like ricotta, cottage cheese, or ice cream,” says Dr. Vishnumohan. 

The good news is that some dairy products contain lower levels of lactose, so you may tolerate these better. Parmesan and mozzarella are examples. Plant-based dairy alternatives are another great option, so you don’t have to miss out. 

woman shopping for milk in the supermarket

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Artificial sweeteners

If you want to lose excess weight, you may be tempted by artificial sweeteners. Yet if you have IBS, these sweeteners can exacerbate symptoms. They often contain polyols, which are difficult for the gut to digest. 

“Think mannitol and sorbitol found in low-calorie sweeteners, sugar-free gums, low-calorie products, and diabetic foods,” says Dr. Vishnumohan.

Got a sweet tooth? Experiment with alternatives like stevia that are gentler on your gut.

Fatty, processed foods

Fatty, processed foods are a prime culprit for IBS symptoms. This includes ready meals and French fries. These foods are empty calories as they contain little nutritional value. Processed foods are linked with a higher risk of health conditions like diabetes and heart disease, according to the CDC. Reducing your intake will benefit your overall health. 

If you’re eating at restaurants and relying on food delivery apps, it’s very hard to know exactly what is in your food,” says Dr. Vishnumohan. “You might be eating fatty or greasy foods and triggering ingredients that could aggravate your IBS symptoms.”

A diagnosis of IBS doesn’t mean you have to deny yourself treats. Try a fakeaway of your favorite meal so you know what’s on your plate.  

fried chicken and fries

(Image credit: Getty Images)

What can you eat with IBS?

When you receive a diagnosis of IBS, a low FODMAP diet can identify your IBS trigger foods. FODMAP is an acronym for specific types of carbohydrates: Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols, according to the Academy of Nutrition and Dietetics.

“The aim of this diet is to eliminate all digestive symptoms by eliminating all FODMAPs, then reintroducing them to see what’s triggering the symptoms,” adds Dr. Vishnumohan. A dietitian can support you in identifying trigger foods while maintaining a diverse, nutrient-dense diet. 

The FODMAP diet is not a long-term solution — it’s a tool to help you identify your personal IBS trigger foods. While you may be tempted to eliminate anything that could cause symptoms, being overly restrictive is not sustainable (and not much fun).  

Thankfully, having IBS doesn’t mean you have to miss out. There are plenty of foods you can consume. “Eat lots of brightly colored fruits and vegetables, whole grains, and any other fresh foods you can tolerate,” advises Dr. Vishnumohan. 

tofu scramble with mushrooms and tomato

(Image credit: Getty Images)

Research in the Journal of Gastroenterology and Hepatology analyzed the FODMAP content in hundreds of fruits and vegetables. Blueberries, lettuce, and spinach all have low levels of FODMAPs so you may find these foods easier to digest. A handy tip is to try cooking fruit and vegetables, which can help you tolerate them.

Soluble fiber is often easier to digest and is beneficial for gut health. Fill up your plate with foods like carrots and oats. The American College of Gastroenterology recommends supplementation with psyllium, a type of soluble fiber which may ease your IBS symptoms. 

Lean, high protein foods are another sound choice. They include chicken, fish, and eggs. Protein is vital for growth and repair and is easy for your gut to tolerate. 

How you eat affects your symptoms too. Take your time and practice mindful eating. You may find small meals aid digestion.

While there are common IBS trigger foods, symptoms are highly individualized, so it’s worth paying attention to what works for you. 

This article is for informational purposes only and is not meant to offer medical advice.

Louise Bond

Louise Bond is a UK-based writer specializing in health and wellbeing. She has over eight years of experience in management within health and care and brings this passion and expertise to her writing. Louise has been published in The Guardian, Planet Mindful and Psychreg among others. She is at her happiest when she is out in nature, whether that’s on an invigorating hike or pottering in the garden.