Irritable bowel syndrome (IBS) is an uncomfortable and frustrating condition that 10 to 15 percent of the global population. With symptoms like diarrhea, constipation, gas, bloating, and stomach cramps, IBS can feel debilitating, but there are ways to find relief from your symptoms.
What you eat can have a large impact on the severity of your symptoms. You may have already tried eating a healthier diet by cutting out fried or processed foods, but many people with IBS still experience symptoms even after making lifestyle changes.
The foods that are causing your symptoms may be ones that you never would have considered, like apples or garlic. With the low-FODMAP diet, you can determine what foods trigger your IBS.
According to a study in PubMed, 76 percent of people with IBS who tried the low-FODMAP diet had a reduction in IBS symptoms. 82 percent saw a decrease in bloating. Flatulence, diarrhea, and constipation can also be significantly reduced with this diet.
This article takes a deeper look into the low-FODMAP diet for IBS, including what it is, how to follow it, and tips for success along the way.
What is the Low-FODMAP Diet?
FODMAPs are carbohydrates that can cause bloating and IBS symptoms because they are hard to digest. Instead of absorbing into your bloodstream, gut bacteria feed on these carbohydrates, producing gas and causing bloating.
The low-FODMAP diet is designed for people with IBS. The goal of this diet is to determine which high-FODMAP foods trigger your IBS symptoms.
Each letter in FODMAP represents a separate category of carbohydrates that can be hard to digest and cause IBS symptoms like bloating, gas, diarrhea, and constipation.
F for Fermentable
Fermentable is the umbrella term to cover all FODMAPs. Fermentable foods contain carbohydrates that lead to bloating and gas when bacteria in your gut break them down.
Note that fermentable is not the same thing as fermented. Fermented foods, like yogurt or kombucha, contain probiotics that may reduce IBS symptoms rather than cause them.
O for Oligosaccharides
Oligosaccharides are a short-chain carbohydrate that is hard to digest. Fructans and galacto-oligosaccharides (GOS) are both in this category.
Foods in this category to avoid: barley, beans, cashews, onions, garlic, pistachios, plums, wheat, and more.
D for Disaccharides
Disaccharides refer to a sugar called lactose. Lactose intolerance may affect up to 65 percent of people, according to MedlinePlus. Lactose is not in all dairy products, like aged cheeses and butter.
Foods in this category to avoid: cottage cheese, cream cheese, ice cream, cow's milk, ricotta, yogurt, and more.
M for Monosaccharides
Fructose, a sugar commonly found in fruits, is a monosaccharide. When a fruit contains more fructose than glucose, it becomes high-FODMAP.
Foods in this category to avoid: agave, apples, asparagus, cherries, high fructose corn syrup, honey, mangoes, pears, watermelon, and more.
P for Polyols
The A in FODMAP stands for and, while the P stands for polyols. Polyols are sugar alcohols that appear in some fruits and vegetables naturally but are also commonly used as sugar alternatives. Sorbitol and mannitol are two categories.
Foods in this category to avoid: apricots, blackberries, cauliflower, mushrooms, nectarines, peaches, prunes, snow peas, sweet corn, sugar alcohol additives, and more.
How to Follow the Low-FODMAP Diet for IBS
The low-FODMAP diet is effective, but it is not necessarily intuitive. When looking at an apple, you may think that an apple is healthy, so it should be fine for this diet. Unfortunately, FODMAPs are not that simple. An apple is high in the monosaccharide called fructose and therefore is not low in FODMAPs and can trigger IBS symptoms.
This diet is a multi-step process that involves an elimination phase, followed by reintroduction and personalization. Here is a guide to starting the low-FODMAP diet:
Step 1: Talk to Your Gastroenterologist
Although the low-FODMAP diet can provide great relief to people with IBS, this diet is not for everyone. The low-FODMAP diet requires planning, trial-and-error, patience, and guidance. Make sure to talk to a gastroenterologist before starting this diet. They will let you know if they think it is right for you based on your IBS diagnosis, symptoms, and symptom severity. Your gastroenterologist may also refer you to a registered dietitian who is experienced with managing IBS symptoms through the low-FODMAP diet for more guidance.
Step 2: Elimination
Although the list of "not allowed" foods is long at first, the goal of this diet is to determine which ones trigger your symptoms. Some FODMAP foods and even whole categories may not bother you. That is why you will need to eliminate all high-FODMAP foods and quantities from your diet temporarily.
During the elimination phase, you will have to stop eating all high-FODMAP foods until your IBS symptoms improve. This may take between 2 and 8 weeks. It will take planning and patience.
Tips for the elimination phase:
Make a meal plan and shopping list. Planning is essential to succeed with this diet. Create a weekly meal plan and a corresponding shopping list of low-FODMAP foods so that you only have to check foods once.
Keep a stockpile of safe foods. Especially during the elimination phase, make sure you have a reliable collection of foods that you already know are safe and low-FODMAP. This diet can be stressful and exhausting, so it is a good idea to pre-verify snack food before you are too hungry to check.
Prep low-FODMAP essentials. Your favorite sauces and prepared foods will likely have high-FODMAP ingredients, like garlic powder or high fructose corn syrup, so you will have to make these staples yourself if you still want to use them. Pick some of your essentials, make them ahead of time by following low-FODMAP recipes you can find online, and store them in your fridge or pantry.
Step 3: Reintroduction
Once your IBS symptoms have improved, and you feel continued relief, you can start slowly reintroducing different FODMAP categories one at a time. In this testing stage, you will eat a food from a FODMAP category and then wait a few days to see if your IBS symptoms return.
If symptoms do return, you will have to go back to the elimination phase. The good news is that now you know an IBS trigger. If symptoms don't return, you can try another food from that same category or move onto the next category. Repeat this process until you finish all categories.
Tips for the reintroduction phase:
Keep a food journal. Writing down what you eat and how you feel each day is essential during the reintroduction phase to track symptoms and find potential triggers.
Look out for high-FODMAP ingredients hiding in ingredients lists. Even if a food seems like it is safe, there may be a high-FODMAP ingredient hiding in it and disrupting success. Check for common ingredients like garlic powder, onion powder, chicory root/inulin, sugar alcohols (end with -ol), high fructose corn syrup, wheat, and honey.
Step 4: Personalization
The personalization phase is the end goal of the low-FODMAP diet. Here, you can begin eating some high-FODMAP foods if they didn't bother you, a lesser quantity of some foods, and low-FODMAP foods. The low-FODMAP diet for IBS is meant to be sustainable and worthwhile after the challenging elimination and reintroduction phases.
Keep in mind that some IBS triggers are not FODMAPs. You can follow this same process to determine other triggers as well.
Tips for the personalization phase:
Use resources. Look at low-FODMAP blogs like Kate Scarlata's for inspiration, read Healthy Gut, Flat Stomach by Danielle Capalino, and download the Monash app for help along the way.
Eat slower and smaller, more frequent meals. If you are still experiencing bloating, try eating your food more slowly to aid digestion. It is also recommended that you eat smaller meals throughout the day instead of large meals to reduce bloating.
Gastroenterologists Can Help Treat IBS
The low-FODMAP diet can be extremely beneficial for people with IBS, but we understand that it can be challenging. At GI Associates, our gastroenterologists can help you through this diet to ultimately help you find relief from your symptoms. If you want to get started on the low-FODMAP diet, have any questions, or are wondering if you have IBS, please schedule an appointment today.