12 Foods to Avoid if You Have Irritable Bowel Syndrome

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Many people who experience irritable bowel syndrome (IBS) can avoid certain dietary triggers, such as gluten, dairy, and caffeine, to prevent IBS symptoms.

Symptoms of IBS include:

Conventional science says there is no cure for IBS. They may prescribe IBS medication that mask symptoms without treating the root cause.

Our holistic health coaches argue that IBS has multiple possible causes, and addressing these causes can reverse IBS. If certain foods are your IBS triggers, avoid those foods, and your IBS shouldn’t bother you.

Below are the 12 foods to avoid if you have IBS and IBS diets that work. There is hope.

At PrimeHealth’s Denver clinic, our experts have helped hundreds of patients like you with digestive problems like IBS. Schedule your free consultation today!

We may receive a small commission from products you purchase via links in this article.

1. Gluten

Gluten is among the most common food intolerances — second most common worldwide, according to many experts. The signs of gluten intolerance include IBS symptoms, such as bloating, gas, nausea, diarrhea, etc.

Common grains containing gluten include:

  • Wheat
  • Barley
  • Rye

Celiac disease is an autoimmune disorder separate from IBS or gluten sensitivity, but it can cause similar symptoms when ingesting gluten. On top of IBS symptoms, celiac disease may result in the immune system attacking its own body, possibly causing long-term damage.

Either way, gluten intolerance and celiac disease can both lead to irritable bowels. Individuals with these conditions can avoid gluten and decrease their risk of IBS symptoms.

Here are gluten-free grains and grain alternatives which can be part of a gluten-free diet:

  • Quinoa
  • Corn
  • Flax
  • Amaranth
  • Arrowroot
  • Gluten-free flours (corn, potato, rice, etc.)

2. Dairy

By some metrics, lactose intolerance is the most common food intolerance in humans. Connected to this fact, dairy is a common IBS trigger. Lactose is a sugar found in milk and other dairy products, such as cheese and ice cream.

When you have lactose intolerance, your body doesn’t make lactase — an enzyme that breaks down lactose in the small intestine. Lactose intolerance symptoms align closely with IBS symptoms: abdominal cramping, flatulence, diarrhea, etc.

Dairy-free alternatives to cow’s milk include:

  • Almond milk
  • Oat milk
  • Rice milk
  • Coconut milk
  • Hemp milk

Rather than lactose, some people are sensitive to casein, a protein in milk. In this case, lactose-free products may not resolve your IBS symptoms.

3. Beans

Beans, beans, the “magical fruit” — this common food group usually provides healthy amounts of fiber and protein to your diet. However, they also contain compounds called oligosaccharides which are resistant to digestion, resulting in bloating, gas, and irregular bowel movements.

Beans, lentils, and legumes may help prevent constipation but can also cause bloating, flatulence, and abdominal cramping.

If you still want beans, try soaking them overnight to reduce oligosaccharide content. Even just 4 hours of soaking can yield favorable results.

4. Insoluble Fiber

Dietary fiber is typically great for preventing IBS symptoms. But soluble fiber is the primary supplement people take to help with IBS.

Insoluble fiber, on the other hand, is especially concentrated in whole grains and vegetables. Although fiber tolerance varies from person to person, insoluble fiber tends to cause IBS symptoms, including either diarrhea or constipation.

What are the worst foods for IBS? The worst foods for IBS are whatever you’re sensitive to. Dairy, gluten, caffeine, fried foods, beans, and anything with insoluble fiber are the most common culprits.

Aim for soluble fiber instead, found in fruits, oats, and beans. (As long as you aren’t sensitive to beans.)

5. Garlic & Onions

Garlic and onions are both delicious flavor additives for your food. However, they also contain fructans, an oligosaccharide, which can cause IBS symptoms.

Raw garlic and onions are generally worse on your digestive system, but even cooked garlic or onion can trigger IBS.

6. Nightshades

In some individuals, nightshade vegetables can cause heartburn, respiratory reactions, rashes, and IBS symptoms. Nightshades are unique because they contain alkaloid compounds.

Nightshade allergy seems to be a rare condition. Those who deal with it are often subject to medical gaslighting due to the newness of the science. Although uncommon, an allergy to nightshade vegetables (of the Solanaceae family) can greatly impact your quality of life.

Nightshade vegetables include:

  • Tomatoes
  • Potatoes
  • Eggplants
  • Peppers
  • Tobacco

If you suspect you’re allergic or sensitive to nightshades, talk to your healthcare provider about an allergy test.

7. Cruciferous Vegetables

Cruciferous vegetables like cabbage and broccoli may trigger IBS symptoms. They are difficult for the body to digest, resulting in bloating, gas, and constipation.

However, cooking  vegetables usually reduces the risk of triggering IBS.

Cruciferous vegetables include:

  • Broccoli
  • Cauliflower
  • Cabbage
  • Arugula
  • Brussels sprouts
  • Kale
  • Radish
  • Turnips
  • Boy choy

8. Caffeine

Maybe that morning cup of joe is causing more harm than good. Caffeinated drinks (including coffee, soda, and energy drinks) can stimulate digestion and reduce constipation but they can also cause diarrhea and other IBS symptoms.

Consider avoiding caffeine if it seems to be an IBS trigger for you. You may experience caffeine withdrawal symptoms, such as headache, fatigue, and irritability.

Other ways to get a boost of energy include:

9. Fried Foods

Western diets are rife with fried foods, such as french fries, corn dogs, classic potato chips, carnival food like funnel cakes, hash browns, hushpuppies, fried chicken, and so much more.

Unfortunately, fried foods are generally considered unhealthy for a whole host of reasons, not the least of which is that they can trigger IBS symptoms.

Such high concentrations of unhealthy fats can slow digestion, leading to abdominal pain, acid reflux, constipation, diarrhea, etc.

Avoid greasy, fatty foods. Opt for healthy fats, like those found in avocados, nuts, seeds, olives (plus olive oil), egg yolks, and fish.

You may also consider alternatives to frying that may be easier on the digestive tract, including:

  • Baking
  • Grilling
  • Steaming
  • Air-frying

10. Sugar Substitutes

“Sugar-free” isn’t always good for your health. Sugar substitutes can cause symptoms of IBS in some individuals.

Commonly sugar substitutes include:

  • Sugar alcohols (xylitol, sorbitol, mannitol, maltitol)
  • Artificial sweeteners (sucralose, acesulfame potassium, aspartame)
  • Natural zero-calorie sweeteners (stevia leaf extract, monk fruit extract)
  • Honey

Sugar alternatives can be found in:

  • Sugar-free candy
  • Gum (both sugar-containing and sugar-free)
  • Diet drinks
  • Mouthwash

Sugar alcohols (polyols) are natural low-calorie sweeteners with essentially only one side effect: your digestive system doesn’t fully digest them (resulting in low calories absorbed), which can cause IBS symptoms.

Artificial sweeteners like aspartame can greatly impact your gut microbiome, possibly resulting in IBS symptoms.

There are other ways to beat the sugar cravings. Check out this Instagram post for more info!

11. Processed Foods

Highly processed foods contain a lot of sodium, sugar (often high fructose corn syrup), unhealthy fats (trans fats), additives, and preservatives. All of these ingredients can result in IBS symptoms by themselves. In conjunction, it’s an IBS stew.

Examples of highly-processed foods include:

  • Pre-packaged foods
  • Premade frozen meals
  • Processed meats like hot dogs or sausage
  • Energy bars and drinks
  • Sweetened cereals
  • Chips

These ultra-processed foods increase your risk for IBS, but also high blood pressure and even cancer.

Preparing your own meals from fresh produce is the best alternative to buying highly processed premade meals. Thrive Market is an online marketplace for organic, non-GMO foods delivered straight to your door!

12. Alcohol

Alcohol is a depressant, meaning it can slow digestion and lead to IBS symptoms. It also leads to dehydration, which can impact your digestion.

Recent research indicates that alcohol can worsen IBS symptoms in people already dealing with irritable bowels.

Avoid or limit alcoholic beverages, and you might reduce your IBS symptoms. You may also consider non-alcoholic alternatives.

Related reading: NAD (Nicotinamide Adenine Dinucleotide): Benefits & How It Works

IBS Diets That Work

Evidence supports these 3 IBS diets may reduce or eliminate IBS symptoms:

The gluten-free and lactose-free diet likely show significant IBS relief because gluten and lactose are such common food triggers. But they aren’t triggers for everyone.

FODMAP stands for “fermentable oligosaccharides, disaccharides, monosaccharides, and polyols. These carbohydrates are generally hard to digest, so they often trigger IBS symptoms.

FODMAP foods may include:

  • Dairy
  • Grains
  • Some fruits, such as apples or watermelon
  • Garlic and onion
  • Cruciferous vegetables
  • Beans, lentils, and legumes
  • High fructose corn syrup
  • Sugar alcohols

You may notice that a lot of these FODMAP foods were previously mentioned in this article. FODMAPs cover a wide range of IBS-triggering foods.

Besides a low-FODMAP diet, you can make natural lifestyle changes and alter your diet in more minor ways to help control your IBS:

  • Increase soluble fiber consumption
  • Eat regular meals without skipping
  • Avoid eating late at night
  • Take IBS probiotics
  • Reduce stress levels
  • Exercise regularly
  • Avoid spicy foods
  • Switch out high-FODMAP fruits for low-FODMAP fruits like blueberries or strawberries
  • Switch out FODMAP veggies for low-FODMAP ones like green beans or sweet potatoes
  • Replace high-sugar fruit juices or energy drinks with water

What foods help settle IBS? Lean protein, healthy fats (like avocado and fish), and soluble fiber should help settle IBS. But it all depends on what is causing your irritable bowels in the first place.

Related reading: Colon Cleansing: Types, Benefits, Dangers & FAQs

How to Get Started

Avoid food triggers, especially FODMAP foods, and stress. Get plenty of sleep, and eat healthy fats and soluble fiber. Those are great starting points.

Functional health coaches and providers can guide you through your recovery from irritable bowel syndrome. Integrative and holistic wellness professionals tend to be more optimistic and respectful towards your health goals, such as reversing IBS.

Schedule a free consultation with PrimeHealth in Denver, Colorado. Our highly-qualified staff have many years of experience in diagnosing and treating gut health problems and autoimmune conditions like inflammatory bowel disease (IBD).

If you don’t want to commit to an appointment, sign up for our free email newsletter to keep up to date with cutting-edge research and helpful health tips.

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