You know the feeling when you eat the “wrong” foods, and it brings on an episode of abdominal pain, cramping, diarrhea, or fatigue.
If you struggle with irritable bowel syndrome (IBS), choosing which IBS foods to eat and which to avoid might feel a lot like detective work. You find yourself examining food labels, studying dietary recommendations, and hoping that your decision won’t cause your symptoms to flare up.
Finding the dietary approach that works best for you doesn’t have to consume your life. In this article, we’ll share seven IBS foods to avoid, how to identify your trigger foods, and how to break free from fearing the foods you eat.
Highly Processed Foods
Eliminating processed foods and choosing healthy, whole foods can be a great first step in eliminating IBS foods to avoid. This means avoiding known inflammatory foods (like fast food, sugar, and processed foods) and identifying specific foods that may trigger inflammation and IBS symptoms.
A diet high in processed foods, sugars, and alcohol can aggravate IBS symptoms  and contributes to a leaky gut . Processed foods feed bacterial gut imbalances and contribute to inflammation. Your body experiences that as stress. Elevated stress levels also increase gut permeability and worsen IBS symptoms [3, 4].
Sugar and Artificial Sweeteners
Sugar and artificial sweeteners can increase gut inflammation and damage the intestinal lining [5, 6]. They can also feed harmful bacteria in the gut. Research has found that artificial sweeteners may alter gut microbiota and cause blood sugar imbalances, triggering an IBS symptom flare-up .
Common artificial sweeteners include mannitol, sorbitol, maltitol, and xylitol. Highly processed foods contain high amounts of sugar (in the form of high fructose corn syrup) and artificial sweeteners.
FODMAP is an acronym for fermentable oligosaccharides, disaccharides, monosaccharides, and polyols. Simply put, FODMAPS are fermentable carbohydrates that can trigger symptoms for some IBS patients.
There’s a significant body of high-quality research that shows a low FODMAP diet helps relieve digestive symptoms and increase quality of life [8, 9, 10, 11, 12, 13, 14, 15, 16]. The low FODMAP diet has also been shown to improve diarrhea and normalize bowel function in IBS patients [17a, 18, 19, 20].
One study found following the low FODMAP approach for six weeks significantly improved gastrointestinal symptoms, stool frequency, and consistency compared with a standard dietary approach [17a].
Some Common High FODMAP foods to avoid:
Vegetables: cauliflower, cabbage, brussels sprouts, broccoli, and asparagus
Fruits: blackberries, apricots, apples, watermelon, plums, and nectarines
Legumes: lentils, beans, chickpeas, and peas
Nuts and seeds: cashews, pistachios, and almonds
Dairy products: brie, ice cream, and yogurt
Grains: wheat and rye
Sweeteners: fructose, high fructose corn syrup, mannitol, xylitol, sorbitol, maltitol, and agave
A 2-3 week trial of the low FODMAP diet can help you determine your sensitivity to high FODMAP foods.
Gluten is a broad name for proteins found in whole grains. The big three gluten whole grains are wheat, barley, and rye. For some people, gluten is an inflammatory food that can trigger IBS symptoms.
There is a lot of controversy surrounding gluten. Gluten often gets a bad rap, but the bottom line is some people can eat gluten without experiencing any adverse side effects while others need to avoid it.
For patients with celiac disease or non-celiac gluten sensitivity consuming gluten can trigger both digestive and non-digestive symptoms consistent with IBS.
It’s unclear why some people are highly reactive to gluten. However, IBS patients should be aware that gluten grains (wheat, barley, and rye) are very high in FODMAPs. In one study in the Journal of Gastroenterology, researchers found that reactions may stem from FODMAPS and not the gluten itself .
If you think gluten is a trigger for your IBS symptoms, it’s a good idea to try a 2-3 week trial elimination to see if your symptoms improve. During this time refrain from eating gluten. If your symptoms do not improve, there’s likely no need to go gluten-free.
Dairy products can also trigger symptoms such as abdominal bloating, pain, cramping, and diarrhea in some IBS patients . There are two potential reasons for this:
Lactose intolerance is caused by a deficiency in the enzyme lactase, which is needed to digest lactose.
Many dairy products are also high in FODMAPs, which may contribute to bacterial overgrowths and inflammation.
If you suspect dairy products contribute to your IBS symptoms, conduct a 2-3 week trial elimination to see if your symptoms improve. For some people, only certain dairy products cause digestive distress. For example, drinking milk might cause bloating, constipation, or diarrhea, whereas eating butter doesn’t trigger any reactions.
While the role of alcohol consumption in IBS symptoms isn’t entirely known , research has found that binge drinking (ingesting four or more alcoholic beverages) and excessive drinking  trigger IBS symptoms .
When it comes to moderate drinking, the picture is less clear. Certain types of alcohol, especially sweet wines, and liqueurs, are high in FODMAPs and may trigger symptoms.
For some patients, it may be helpful to temporarily abstain from drinking alcohol while their gut heals. Others may find they can safely consume moderate amounts of alcohol. Trial and error is the key to understanding how much alcohol you can safely consume.
Caffeine can have a laxative effect in some individuals . This can be problematic for those individuals who also have IBS-D. For others, the key to your coffee consumption is likely moderation.
Caffeine increases cortisol (a stress hormone) . Stress is a known IBS trigger, and chronic stress can make it difficult to resolve your leaky gut, IBS, and other gut health issues [28, 29]. Keeping your coffee consumption in check may help reduce stress-related IBS triggers.
What Foods Are Safe To Eat with IBS?
Now that we’ve covered the IBS foods to avoid, let’s take a look at what you can eat. The basics for an IBS diet are to choose fresh, whole, unprocessed foods, reduce high-FODMAP foods, and identify your personal food triggers. The following foods provide a good starting point to a healthy diet.
- Meat, poultry, fish, eggs, seafood (without marinades, sauces, breading)
- Rice, corn, oats, and quinoa
- A variety of low FODMAP vegetables, including zucchini, green beans, bok choy, red bell peppers, carrots, tomatoes, cucumbers, and lettuce
- A variety of low FODMAP fruits, including blueberries, strawberries, kiwi, bananas, oranges, and cantaloupe
- Lactose-free dairy products
- Nuts and seeds, including macadamia nuts, pecans, almonds, and walnuts (in small quantities)
Here are a few helpful tips that can help you implement dietary changes.
Keep it simple. Making dietary changes can be overwhelming, but it doesn’t have to be. Choose a few essential foods and recipes to start with. It’s okay to repeat meals when you’re first starting. It will be easier to expand your menu options and try new recipes once you feel comfortable identifying your food triggers.
Plan ahead. Remove the foods that may be tempting and the IBS foods you want to avoid. Stock your pantry and refrigerator with the foods you want to focus on eating. Batch cook a few of your staple meals and stock them in your freezer.
Be as strict as possible for 3-4 weeks. During this time, adhere to your plan as closely as possible. If your dietary changes are helpful, your symptoms should improve during this time. Then, you can slowly reintroduce one food at a time to identify your food triggers.
Don’t fear your food. Don’t fall into the trap of thinking you have to avoid problem foods forever. We encourage our patients to have the fewest dietary restrictions possible and develop a healthy non-fear-based relationship with food. As your digestive tract heals, the foods you can eat may change. You may find that you can eat moderate amounts of food that caused a reaction six months ago.
Diet as Part of Your IBS Treatment Plan
Focusing on an unprocessed, whole foods-based diet can eliminate many of the adverse symptoms IBS patients experience. The Paleo diet and the low FODMAP diet offer great places to start.
In addition to diet, patients should also focus on lifestyle management by getting adequate sleep, moderate exercise, and managing stress.
For patients who need additional treatment support, combining probiotic supplementation with a low-FODMAP diet has been shown to improve digestive [30, 31, 32, 33, 34] and non-digestive symptoms of IBS [35, 36].
Understanding which IBS foods to avoid can help eliminate guesswork, reduce the fear of food, and provide a powerful tool to restore gut health. If you’d like more information on treating your IBS symptoms, contact us today.