Why Raw Vegetables May Be Aggravating Your IBS

Updated on February 04, 2023

Medically reviewed by Robert Burakoff, MD, MPH

If you have irritable bowel syndrome (IBS), eating raw vegetables may make your symptoms worse. If you can’t tolerate raw onions, garlic, or broccoli, strategies like cooking and juicing can be a more IBS-friendly way to get the nutritional benefits of veggies. There are also certain raw veggies, like carrots and green beans, that some people with IBS find easier to tolerate.

This article will explain why raw vegetables can trigger IBS symptoms and how to figure out which veggies don’t work for you. You’ll also learn some alternative ways to get your veggies that are less likely to trigger IBS symptoms.

Woman cutting vegetables — Leren Lu / Photodisc / Getty Images

What Is IBS?

Why Raw Vegetables Can Trigger IBS

Research on IBS has shown that people with the condition often notice that certain foods make their symptoms worse. That said, there's no one food that is always a trigger for every person with the condition.

Still, some people with IBS do get an increase in symptoms like bloating, gas, constipation, and/or diarrhea after they eat raw vegetables.

There are a few reasons why raw veggies could contribute to IBS symptoms:

Fiber. When you eat raw veggies, your digestive system is tasked with breaking down the food components. The tough fiber in veggies (cellulose) is not broken down and the "roughage" can irritate the digestive tract as it passes through.
FODMAPs. FODMAP stands for different types of carbohydrates: fermentable oligosaccharides, disaccharides, monosaccharides, and polyols. Since these carbohydrates are poorly absorbed by the small intestine, they can trigger IBS symptoms in some people.
Food volume. When you are eating a salad or raw vegetables, you're usually eating a large volume of food. According to the FODMAP diet theory, this can increase the amount of gas and the osmotic "load in your gut and contribute to IBS symptoms.

Raw may not be the problem—you may have trouble with certain vegetables no matter how you eat them.

For example, mushrooms, celery, cauliflower, onions, and snow peas are high-FODMAP foods that can trigger GI symptoms in people with IBS (and even some people who don't have it).

Figuring Out Which Raw Vegetables You Can Have With IBS

Everybody is different, and IBS is different for every person that has the condition.

If raw veggies don’t make your symptoms worse, you don’t need to cut them out. If you think that veggies could be contributing to your symptoms, you’ll need to do a little experimenting to find out which ones are troublesome for you.

You can start by cutting out certain vegetables to see if your symptoms get better. It can take time and a lot of trial and error, but paying attention to how your body reacts to certain vegetables will help you figure out which ones you’ll want to avoid.

As a starting point, use the FODMAPs food list to figure out which veggies in your diet might be the source of your symptoms.

What Research Says About a Low-FODMAP Diet

Raw Vegetables That Can Trigger IBS Symptoms

Artichokes
Asparagus
Beets
Broccoli
Bok choy
Brussels sprouts
Cabbage
Cauliflower
Celery
Coleslaw/sauerkraut
Corn
Garlic
Mushrooms
Okra
Onions
Peas (snow, sugar snap)
Scallions (white parts)
Shallots

Leafy raw vegetables like kale, lettuce, and arugula are low-FODMAP, but some people with IBS and other GI disorders find them hard to digest.

Best Foods for IBS

How to Make Vegetables IBS-Friendly

If you find that you feel better not eating certain raw vegetables, you may worry that not including them in your diet will make it harder to meet your nutritional needs and goals.

While you may not want to eat them raw, there are some other ways you can try preparing veggies that may make them less likely to trigger IBS symptoms:

Prepping your veggies by cutting them up into smaller pieces and removing the "tough bits"—think skin, seeds, stems, and stalks—can go a long way to making them easier on your digestive system.
Cooking your veggies instead of eating them raw can also be helpful. Similar to starting the breakdown process by cutting up and peeling food, the heat from cooking heat also helps break down the food and gives your gut a head start. Cooked veggies put fewer demands on your digestive system than raw ones and still provide most of the nutritional benefits.
Puréeing cooked veggies is another great way to do some of the digestive work for your gut. You might automatically think of baby food, but veggie purées are a perfect base for "grown-up" foods like smoothies and creamy soups.
Juicing is another way to get veggies in your diet if you have IBS. Like cooking, juicing a veggie starts the digestion process. You’ll lose most of the fiber content, but juicing can be a more comfortable way to access the other nutritional benefits of raw vegetables. If you'd rather have something warm, try making vegetable broths and stocks.

Some people with IBS can tolerate certain veggies raw, like carrots, bell peppers, green beans, radishes, and tomatoes.

What to Do If Diet Changes Don't Help With IBS

If your IBS symptoms are continuing or getting worse even after you’ve changed your diet, see a gastroenterologist. Your symptoms may not be from IBS and could be from another GI condition such as celiac disease or chronic pancreatitis.

Summary

Some people with IBS find that eating raw vegetables triggers symptoms. You may want to try cutting out certain raw vegetables from your diet to figure out which ones are most likely to bother you. Cooking or juicing veggies that you can’t eat raw can jumpstart the process of breaking them down, making it easier on your digestive system.

If your IBS symptoms are not getting any better despite making changes to your diet, talk to your provider or gastroenterologist. It’s possible that you need another treatment approach to manage your IBS, or that your symptoms are caused by another GI condition.

What to Eat If You Have IBS

8 Sources

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

Ligaarden SC, Lydersen S, Farup PG. Diet in subjects with irritable bowel syndrome: A cross-sectional study in the general population. BMC Gastroenterology. 2012;12(1). doi:10.1186/1471-230x-12-61
Jarvis MC. Structure of native cellulose microfibrils, the starting point for nanocellulose manufacture. Philos Trans A Math Phys Eng Sci. 2018;376(2112):20170045. doi:10.1098/rsta.2017.0045
Monash University. FODMAPs and irritable bowel syndrome.
Dugum M, Barco K, Garg S. Managing irritable bowel syndrome: The low-FODMAP diet. Cleve Clin J Med. 2016;83(9):655-62. doi:10.3949/ccjm.83a.14159
Vanhauwaert E, Matthys C, Verdonck L, De Preter V. Low-residue and low-fiber diets in gastrointestinal disease management. Advances in Nutrition. 2015;6(6):820-827. doi:10.3945/an.115.009688
Memorial Sloan Kettering Cancer Center. Eating guide for pureed and mechanical soft diets.
Canadian Society of Intestinal Research. IBS Diet: The foods you can eat.
Pyo YH, Jin YJ, Hwang JY. Comparison of the effects of blending and juicing on the phytochemicals contents and antioxidant capacity of typical korean kernel fruit juices. Prev Nutr Food Sci. 2014;19(2):108-14. doi:10.3746/pnf.2014.19.2.108

By Barbara Bolen, PhD
Barbara Bolen, PhD, is a licensed clinical psychologist and health coach. She has written multiple books focused on living with irritable bowel syndrome.

See Our Editorial Process

Meet Our Medical Expert Board

Share Feedback

Was this page helpful?

Thanks for your feedback!

What is your feedback?