Irritable bowel syndrome (IBS) is a common digestive illness affecting between 5% and 10% of people worldwide. While we're still learning about the exact causes of IBS, it's thought that it's due to a miscommunication between the gut and the brain.

Many different factors can affect the severity of IBS symptoms, from sleep quality to stress levels to diet. The specific foods to avoid with IBS vary between individuals, and the foods that trigger symptoms in one person may be well-tolerated by someone else. That's why lifestyle and diet changes need to be personalized to the individual to prevent IBS flare-ups.

This article will provide a list of common IBS trigger foods, IBS-friendly food swaps, and tips for identifying your own personal food triggers to manage your IBS symptoms.

What Is IBS and How Does It Affect Digestion?

IBS is a disorder of gut-brain interaction (DGBI). This means that while there is nothing structurally wrong with the digestive system, people still experience debilitating symptoms like gas, bloating, abdominal pain, and altered bowel habits due to dysregulation of the gut-brain axis (in other words, a miscommunication between the gut and the brain).

The gut microbiota (the community of trillions of microorganisms living in your large intestine) may also play a role in IBS, with studies showing that people with IBS have reduced levels of good gut bacteria like Bifidobacterium and Faecalibacterium. However, the gut microbiota varies significantly between individuals, so we still don't have a clear idea of what a "healthy microbiota" looks like. 

In addition, post-infectious IBS is common. Post-infectious IBS may arise because the gut fails to return to its original state (including the balance of microbes in the gut) after the infection clears.

There's also a relationship between. exercise and gut health. High-intensity exercise, such as running, may worsen digestive symptoms like diarrhea and urgency, while gentle movement, like walking or yoga, may relieve symptoms like gas, bloating, and constipation.

A key component of IBS is visceral hypersensitivity. Studies have shown that people with IBS have extra-sensitive digestive tracts, which can lead to normal digestive processes being perceived as painful. This explains why certain foods, such as gas-producing foods, trigger symptoms.

IBS is more common among women, with studies showing a female-to-male ratio of 2-2.5:1 when it comes to seeking medical care for IBS. In addition, some research indicates that the hormonal changes during pregnancy and childbirth can trigger IBS symptoms.

Why Certain Foods Trigger IBS Symptoms

Foods high in FODMAPs are a common trigger for IBS symptoms. FODMAP stands for Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols. These short-chain carbohydrates resist digestion, instead moving into the large intestine intact. Here, they get fermented by your gut bacteria, producing gas and, in some cases, drawing water into the large intestine.

For most people, the gas produced by FODMAP fermentation doesn't cause a problem. But for people with visceral hypersensitivity (such as those with IBS), the sensation of the gas pushing on the intestinal walls can be perceived as extremely painful. In addition, the water being pulled into the digestive system by FODMAPs, like lactose and polyols, can cause diarrhea. For this reason, a special diet called the low FODMAP diet is often used to help people with IBS determine their food triggers.

Unfortunately, many people start to exhibit significant food avoidance due to this link between food and symptoms. However, in many cases, people can expand their diets by identifying which specific foods trigger they’re not tolerating well.

IBS Trigger Foods to Avoid

It's important to note that when it comes to IBS trigger foods, every person is different. A food that triggers symptoms in one person may be perfectly tolerable to another. The lists below are intended to serve as a starting point for identifying your trigger foods. Working with a dietitian for IBS is the best way to identify your personal food triggers and help manage IBS flare-ups. They can help you make diet changes followed by a structured reintroduction to determine which foods may cause digestive symptoms.

High-FODMAP Foods

There are five types of FODMAPs: Fructans, galacto-oligosaccharides (GOS), lactose, excess fructose, and polyols (mannitol and sorbitol).

Here are some of the highest FODMAP food sources of each group:

Fructans:

  • Wheat (e.g., bread, pasta)
  • Onions
  • Garlic
  • Shallots
  • Leeks (the white portion)
  • Artichoke
  • Brussels sprouts
  • Cabbage
  • Dried fruit

GOS:

  • Kidney beans
  • Black beans
  • Cashews
  • Cruciferous vegetables (like broccoli)
  • Split peas
  • Falafel (chickpeas)
  • Pistachios
  • Soy milk

Lactose:

  • Cream cheese
  • Custard
  • Evaporated milk
  • Fresh cheeses
  • Cow's and goat milk
  • Cottage cheese
  • Ice cream
  • Yogurt

Excess fructose:

  • Apples
  • Asparagus
  • Pears
  • Blackberries
  • Mangos
  • Cherries
  • Figs
  • Pears
  • Watermelon
  • Fruit juice
  • Honey
  • High-fructose corn syrup

Polyols:

  • Mushrooms
  • Apple
  • Apricot (dried)
  • Peaches
  • Prunes
  • Coconut milk
  • Artificial sweeteners
  • Sugar alcohols

For a list of other foods high in FODMAPs, check out our blog post about the low FODMAP diet.

Fatty and Fried Foods

There are several reasons high-fat foods and processed foods may worsen IBS symptoms. First, fat slows down digestion. This can cause stool to sit in your digestive tract for longer. As it sits, water is reabsorbed, leading to stool that is harder and difficult to pass. For individuals prone to constipation, this can exacerbate their symptoms.

In addition, over one quarter of people with diarrhea-predominant IBS (IBS-D) also experience bile acid malabsorption (BAM). When you eat fat, your gallbladder releases bile acids into the small intestine to help break it down. Typically, about 95% of those bile acids are reabsorbed in the ileum (the last part of the large intestine). However, when people have BAM, excess bile acids spill into the large intestine instead of being reabsorbed. This can irritate the colon, leading to the secretion of water and electrolytes, along with increased gut motility. The result? Urgent, watery diarrhea.

Eating fatty and fried foods leads to an increase in bile acid release, effectively increasing the load that needs to be reabsorbed. In people with BAM, the ileum can't handle the bile acid load, so more bile acids wind up in the large intestine. For that reason, people with BAM are often advised to follow a lower-fat diet to manage their symptoms. In some cases, they may also need to take bile acid sequestrant medications to reduce the incidence of diarrhea. Note that BAM is a condition separate from IBS, though the overlap between the two is high.

Here are some fatty and fried foods you may need to limit if you have IBS-D and BAM:

  • Fatty cuts of beef, pork, or lamb
  • Sausages 
  • Bacon
  • Hot dogs
  • Chicken or turkey with skin
  • Fried meats
  • Whole milk
  • Cream
  • Half-and-half
  • Full-fat cheese
  • Butter
  • Ice cream
  • French fries
  • Onion rings
  • Burgers
  • Pizza
  • Nachos
  • Doughnuts
  • Churros
  • Fried pastries
  • Potato chips
  • Large amounts of cooking oil (like olive oil and canola oil)
  • Mayonnaise

Remember, fat is essential for the absorption of many vitamins, as well as hormone production. Therefore, you should still include some fat in your diet. We'll provide some healthy fat options in the next section.

Dairy Products

Not everyone with IBS needs to avoid dairy products. However, people with IBS who also have lactose intolerance may need to limit their intake of certain dairy products. 

Lactose is a type of naturally occurring sugar found in dairy products that requires the lactase enzyme to break it down. In people who don't produce enough of this enzyme, lactose travels to the colon intact. This draws water into the colon. It's also fermented by the gut bacteria, producing gas. This leads to the classic symptoms of lactose intolerance, like gas, bloating, and diarrhea.

Here are some higher-lactose dairy products you may need to limit if you have lactose intolerance:

  • Milk (whole, 2%, 1%, and skim)
  • Half-and-half
  • Heavy cream
  • Whipping cream
  • Cream cheese
  • Ricotta
  • Cottage cheese
  • Marsarpone
  • Paneer
  • Queso fresco
  • Regular yogurt
  • Kefir
  • Ice cream
  • Condensed milk
  • Evaporated milk
  • Milk powder
  • Whey protein concentrate

Not all dairy products contain significant amounts of lactose. We'll provide some lower-lactose dairy and dairy alternatives in the next section.

Caffeinated and Carbonated Beverages

The relationship between caffeine intake and IBS is complex. While caffeine can speed up gut motility, worsening urgency and diarrhea in people with IBS-D, it may actually be beneficial for people with constipation-predominant IBS (IBS-C). You may need to experiment with varying amounts of caffeine to see how your digestive system reacts. 

In general, it's best to limit your caffeine intake to 400 mg or less (about two to three 12-ounce cups of coffee) daily to prevent it from interfering with your sleep.

Here are some foods with caffeine that you may need to avoid if you have IBS-D:

  • Coffee
  • Tea (especially black, green, oolong, and yerba maté)
  • Chocolate (especially dark chocolate)
  • Hot cocoa
  • Chocolate milk
  • Chocolate-flavored desserts
  • Colas
  • Energy drinks
  • Energy shots
  • Preworkout supplements
  • Weight loss or "fat burner" supplements
  • Certain pain relievers

Carbonated beverages can also exacerbate IBS symptoms. Drinking carbonated beverages introduces excess air into your digestive tract. If you have a sensitive digestive system, this can cause painful gas and bloating.

Here are some carbonated beverages to limit if you're prone to gas and bloating:

  • Sodas (regular and diet)
  • Sparkling water
  • Seltzer
  • Energy drinks
  • Beer
  • Hard seltzers
  • Champagne and sparkling wine
  • Cider
  • Kombucha
  • Sparkling probiotic sodas (these are also often high in prebiotics, which get fermented by your gut bacteria and may worsen gas and bloating)

Artificial Sweeteners

Certain artificial sweeteners contain sugar alcohols (also known as polyols). If you're sensitive to them, they can cause gas, bloating, and diarrhea.

Here are some foods and ingredients with polyols that you may need to limit with IBS-D:

  • Xylitol
  • Sorbitol
  • Mannitol
  • Isomalt
  • Maltitol
  • Sugar-free candies
  • Sugar-free gum
  • Sugar-free ice cream
  • Sugar-free baked goods
  • Certain protein bars or meal replacement bars
  • Keto products
  • Flavored waters
  • Sugar-free sports drinks
  • Certain chewable vitamins
  • Cough drops and throat lozenges
  • Sugar-free syrups

Alcohol

Alcohol can irritate the digestive system and cause inflammation, which may worsen IBS symptoms. Here are some alcoholic beverages to consider limiting, both for IBS management and overall health:

  • Beer
  • Cider
  • Cocktails (like margaritas and daiquiris — these are also high in sugar, which can worsen IBS symptoms)
  • Spirits (like rum and whiskey)
  • Dessert wine
  • Sparkling alcoholic drinks (like prosecco and sparkling wine)
  • Hard seltzers

IBS-Friendly Food Swaps to Consider

Fortunately, there are plenty of IBS-friendly foods that you can incorporate into your eating plan. Here are some food swaps to consider for each of the IBS trigger groups.

Lower-FODMAP Foods

Fruits:

  • Blueberries
  • Breadfruit
  • Starfruit
  • Dragonfruit
  • Lemons
  • Limes
  • Kiwi fruit
  • Papaya

Vegetables:

  • Bamboo shoots
  • Bean sprouts
  • Green beans
  • Green bell peppers
  • Carrots
  • Collard greens
  • Baby corn (canned, drained)
  • Cucumber
  • Kohlrabi
  • Leek (green portion only)
  • Lettuce
  • Olives
  • Spring onions (green tops only)
  • Parsnips
  • Potatoes
  • Radishes
  • Spinach
  • Swiss chard

Grains:

  • 100% spelt sourdough (1 slice per meal)
  • Gluten-free bread (2 slices per meal)
  • Gluten-free pasta
  • Gluten-free flour
  • Buckwheat flour
  • Corn flour
  • Rice flour
  • Millet
  • Rice vermicelli noodles
  • Rolled oats (½ cup per meal)
  • Quinoa
  • Brown rice
  • White rice
  • Wild rice
  • Corn tortillas
  • Popcorn
  • Rice cakes

Proteins:

  • Poultry (chicken, turkey)
  • Seafood (fish, shrimp, crab, scallops)
  • Meat (beef, lamb, pork)
  • Eggs
  • Firm tofu
  • Tempeh
  • Canned, drained chickpeas (¼ cup per meal)
  • Canned, drained lentils (¼ cup per meal)
  • Whey protein isolate
  • Egg white protein
  • Rice protein

Dairy and dairy alternatives:

  • Lactose-free milk and yogurt
  • Hard cheeses
  • Plant-based milks (almond, macadamia, hemp, rice)
  • Soy milk (if made from soy protein)

Nuts and seeds:

  • Hazelnuts
  • Macadamia nuts
  • Peanuts
  • Pecans
  • Walnuts
  • Chia seeds
  • Hemp seeds
  • Pumpkin seeds
  • Sesame seeds

For a more comprehensive list of lower-FODMAP foods, check out our low FODMAP food list blog post.

Lower Fat Foods

Here are some lower-fat foods to include if fat is a trigger for you:

  • Skinless chicken or turkey breast
  • White fish (like cod or tilapia)
  • Shellfish (like shrimp or scallops)
  • Egg whites
  • Firm tofu
  • Tempeh
  • Canned, drained lentils (limit to ¼ cup per meal if sensitive to GOS)
  • Canned, drained chickpeas (limit to ¼ cup per meal if sensitive to fructan or GOS)
  • Low-fat dairy (choose lactose-free if you're lactose intolerant)
  • Almond milk
  • Rice milk
  • Soy milk (if made from soy protein)
  • Oat milk (limit if you're sensitive to fructans)
  • Oats
  • Quinoa
  • Rice
  • Gluten-free bread
  • Gluten-free pasta
  • Potatoes (avoid frying)
  • Sweet potatoes (limit to TK if sensitive to TK)
  • Fruits and vegetables (naturally low in fat; choose low FODMAP options if sensitive to FODMAPs)
  • Rice cakes
  • Air-popped popcorn

Use small amounts of healthy fats (like avocado oil or olive oil) in your cooking. Remember, fat is needed for vitamin absorption, so it's important to include some in your diet. Stick to baking, grilling, steaming, or air-frying to limit the amount of fat needed while cooking.

Lower-Lactose Dairy and Dairy Alternatives

Dairy is a good source of calcium and protein. Here are some low-lactose dairy products and dairy alternatives to include in your diet if you're lactose intolerant:

  • Aged hard cheeses (like cheddar and Swiss)
  • Butter
  • Greek yogurt (often better tolerated due to live bacterial cultures breaking down lactose, but varies from person to person)
  • Lactose-free yogurt
  • Lactose-free milk
  • Lactose-free cottage cheese
  • Lactose-free ice cream
  • Almond milk
  • Soy milk (if made from soy protein)
  • Rice milk
  • Hemp milk
  • Macadamia milk

Low-FODMAP Sweeteners

While artificial sweeteners containing sugar alcohols may trigger IBS symptoms, there are plenty of low-FODMAP sweeteners available:

  • Acesulfame-K
  • Allulose
  • Aspartame
  • Brown sugar
  • Beet sugar
  • Demerara sugar
  • Dextrose
  • Glucose syrup
  • Icing sugar
  • Maple sugar
  • Monk fruit extract
  • Palm sugar
  • Pure maple syrup
  • Raw sugar
  • Rice malt syrup
  • Saccharin
  • Stevia
  • Sucralose
  • White sugar

IBS-Friendly Alcoholic Beverages

Here are some IBS-friendly alcoholic beverages:

  • Dry red or white wine
  • Clear spirits (vodka, gin, tequila)
  • Light beer (although it is still carbonated, so it could increase the likelihood of gas and bloating)

It's important to note that even moderate alcohol intake increases health risks compared to not drinking. If you do choose to consume alcohol, try to stick to one drink per day or less if you're female, and two drinks or less per day if you're male.

How to Identify Your Personal IBS Food Triggers

If you feel overwhelmed looking at all the foods that could trigger IBS symptoms, you're not alone. Fortunately, it's very unlikely that all the foods listed above will trigger your symptoms. That's why it's so important to learn which specific foods are triggers for you.

The best way to identify your personal triggers is through an elimination diet with a structured food reintroduction accompanied by food and symptom tracking. This is where you will temporarily eliminate potential food triggers until your symptoms are under control, then reintroduce the trigger foods one at a time to see how your body reacts.

One of the most evidence-based elimination diets for IBS is the low FODMAP diet. During this diet, you will temporarily replace high FODMAP foods with lower FODMAP alternatives for two to six weeks (until symptoms improve). Then you'll reintroduce foods one FODMAP group at a time to determine which groups you're sensitive to. 

Keeping a food and symptom journal throughout elimination and reintroduction is critical for drawing relationships between food, lifestyle, and your symptoms. Here are some things you may wish to track:

  • Foods eaten (including portion size and timing)
  • Symptoms (type, severity, and timing)
  • Bowel movements (frequency and consistency)
  • Sleep (duration and quality)
  • Stress levels
  • Exercise/movement
  • Routine changes (e.g., travel)
  • Medications
  • Supplements
  • Other treatments (e.g., massage)

Tracking these things can help you see whether your symptoms are caused by what you're eating or if they're caused by lifestyle factors such as stress and poor sleep.

Once you've determined your individual IBS triggers, you can create a personalized plan for managing your symptoms. This could involve completely avoiding certain foods, minimizing your intake of specific foods, or using digestive enzymes to break down the FODMAP groups to which you're sensitive.

Remember, very restrictive diets can negatively impact a person's quality of life, so it's important to reduce stress associated with eating by liberalizing your diet and eating as many different foods as possible. A registered dietitian familiar with the dietary guidelines for your life stage can help you develop a plan to manage your symptoms while enjoying the foods you love.

Managing IBS Through Diet and Enzymatic Support

If you find out that you're sensitive to FODMAPs through the process of elimination and reintroduction, you may worry that you'll need to avoid certain FODMAP groups forever. However, depending on which FODMAP groups you're sensitive to, there may be digestive enzymes that can help you enjoy those high FODMAP foods without symptoms.

FODZYME is a digestive enzyme supplement that contains three digestive enzymes:

  • Lactase (to break down the lactose found in many dairy products).
  • Alpha-galactosidase (to break down the GOS found in legumes and certain nuts).
  • Fructan hydrolase (to break down the fructans found in wheat, onions, and garlic).

When you sprinkle FODZYME on your food, it starts to break down the lactose, GOS, and fructans so that they're neutralized by the time they reach your large intestine, helping to control gut symptoms like gas, bloating, and abdominal discomfort.

FAQs About IBS Trigger Foods

What foods commonly trigger IBS symptoms?

IBS triggers are highly individual, and what triggers symptoms for one person may be fine for another person. Some common IBS triggers include foods high in FODMAPs (fermentable carbohydrates), fried and fatty foods, dairy products that contain lactose, caffeine, carbonated beverages, artificial sweeteners (especially sugar alcohols), and alcohol.

Is lactose-free dairy ok for IBS?

People with IBS and lactose intolerance can include lactose-free dairy in their diets without experiencing symptoms. If you're not sensitive to lactose, you should be able to include lactose-containing dairy in your diet regardless of whether or not you have IBS.

How soon after eating do IBS symptoms start?

Most people with IBS experience symptoms several hours or even up to a full day after a triggering meal. This is related to the time it takes for the meal to be digested. If FODMAPs are responsible for your symptoms, it takes several hours for them to reach the large intestine (where they're fermented, causing symptoms). 

It's worth noting that people with IBS often have an exaggerated gastro-colic reflex (the movement of digestive tract muscles that propel food through the digestive system). Eating large meals or meals high in fat can trigger this reflex more strongly, which can propel food from the previous meal into the large intestine, where it may cause symptoms related to the previous meal.

How can I figure out which IBS foods trigger my symptoms?

A common way to figure out which IBS foods trigger your symptoms is to do an elimination diet followed by a structured reintroduction. For example, the elimination phase of the low FODMAP diet lasts for two to six weeks, followed by the reintroduction phase, which takes eight to twelve weeks. During the reintroduction phase, you will reintroduce each FODMAP group one at a time to determine which foods and portions you tolerate. Many people find it useful to keep a food and symptom diary during the elimination and reintroduction phases, as it helps them see the relationship between their symptoms and the foods they eat.

Take Control of Your Gut Health

Living with IBS doesn't have to mean giving up the foods you love. By understanding your individual triggers and making simple swaps, you can reduce uncomfortable digestive symptoms while still enjoying a varied diet.

Tools like FODZYME can also help by breaking down FODMAPs, giving you more flexibility and confidence with your meals.

Try FODZYME today and take the first step towards a more varied diet.