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Managing Irritable Bowel Syndrome (IBS) Symptoms with a Low FODMAP Diet

    Do you have Irritable Bowel Syndrome (IBS) and are you wondering what you can do to ease your symptoms? You’re not alone! About 10-15% of people in the United States have IBS, experiencing symptoms like uncomfortable gas, painful bloating, and diarrhea on a daily basis.

    Read on to discover how a low FODMAP (Fermentable, Oligosaccharides, Disaccharides, Monosaccharides, And polyps) diet can help manage IBS symptoms , and what you need to know before starting a low FODMAP diet!

    What Are FODMAPs and What Is A Low FODMAP Diet? 

    FODMAPs are a group of short-chain carbohydrates that are tough for your gut to absorb, leading to digestive issues and intestinal distress for some individuals. The acronym “FODMAP” stands for… 

    • Fermentable – FODMAP carbohydrates enter your large intestine and your gut bacteria eat them, breaking them down in a process called fermentation. Your gut bacteria then produce gas as a by-product! 
    • Oligosaccharides – This category can be split into 2 groups: fructans and galactans. Fructans are found in high concentrations in gluten-containing products (eg. wheat, barley, rye), as well as foods like onion, garlic, and dried fruit. Galactans are found in high concentrations in dairy products, and various nuts and legumes. 
    • Disaccharides – One of the most well-known disaccharide is lactose, which is found in milk, yogurt, soft cheese, and various other dairy products. In order to be absorbed, lactose requires the digestive enzyme lactase (without lactase enzymes, your body has more difficulty processing higher lactose products, which means more symptoms!) 
    • Monosaccharides – Fructose is a monosaccharide that is naturally found in fruits. More equal amounts of glucose are needed in food to help with fructose absorption in the small intestine; excess fructose may cause gastrointestinal issues in some individuals. 
    • AndPolyols – Polyols are sugar alcohols that can be found in several fruits, vegetables, and artificial sweeteners. They can be problematic for people with more sensitive guts, as they are only partially absorbed in the small intestine – the rest goes to the large intestine, where they are fermented by your gut bacteria. 

    Many people believe that a low FODMAP diet means completely eliminating high FODMAP foods and only eating low FODMAP foods, but that isn’t true! A low FODMAP diet is NOT an elimination diet (nor a weight loss plan), and it’s much more complex than you may think. It consists of three phases: 

    • Low FODMAP phase/“elimination phase” (4-6 weeks): This phase involves reducing the number of high-FODMAP foods you consume and focusing more on low FODMAP foods. Thus helps to determine if high FODMAP foods are actually triggering your IBS symptoms. Why is this phase so short? Even though reducing moderate-high FODMAP foods can help with IBS and painful bloating, long-term elimination can make changes to your gut microbiota and possibly make your digestive issues worse later on!
    • FODMAP reintroduction phase/“challenge phase”: This phase involves slowly adding high FODMAP foods back into your diet to see which particular FODMAP groups are your food triggers
    • Adapted FODMAP diet/“personalization phase”: This phase involves incorporating a mix of tolerated high FODMAP foods and low FODMAP foods into your diet, allowing those with IBS (and other conditions, such as SIBO) to alleviate their gut symptoms by figuring out their specific food triggers!

    Why Are FODMAPs Important for Reducing IBS Symptoms? 

    Although we don’t fully understand what causes IBS, several factors are suggested to have a significant effect on IBS symptoms:

    As a result, diet has been suggested as a potential way to alleviate IBS symptoms.

    So, why the focus on FODMAPS? 

    As discussed above, FODMAPS are poorly absorbed by the small intestine. Your small intestine draws in extra water to move FODMAPS to your large intestine where your bacteria eat them and produce gas as a byproduct. As a result, you may experience bloating, abdominal pain, diarrhea, etc. 

    So, by reducing the amount of carbohydrates that are being poorly absorbed and digested, it’s believed that individuals with more sensitive guts (eg. those with IBS) may experience less symptoms, because there is less water being drawn in and less gas being produced! 

    And in fact, in this 2016 review, it was found that after following a low FODMAP diet, up to 86% of patients with IBS experienced improvements in… 

    • Abdominal pain 
    • Bloating 
    • Constipation
    • Diarrhea
    • Overall gastrointestinal issues

    Foods High in FODMAPs

    Not sure which foods are high in FODMAPs? Here is a list of just a few: 

    • Fruits with an excess of fructose (eg. apples, cherries, mangoes) 
    • Garlic, onions, legumes and pulses
    • Cashews and pistachios 
    • Grains and cereals rich in fructan 
    • High-lactose foods (eg. milk, yogurt, soft cheese)
    • Honey, high fructose corn syrup

    So, Where Do I Start? 

    If you’re considering going on a low-FODMAP diet, reach out to a registered dietitian who is trained in FODMAPs first to figure out if this is the right diet for you. The list of symptoms for each individual with IBS looks different, so there isn’t a “one-size-fits-all” solution that works for everyone! 

    FODMAPs naturally occur in many foods that provide you with the important vitamins and minerals you need, so starting a low FODMAP diet without the guidance of a registered dietitian may result in inadequate nutrient intake. Not only can a FODMAP-trained professional help you create a low-FODMAP eating plan that is safe to follow and prevents long-term diet restriction, they can also provide you with plenty of support and guidance along the way!

    Remember: the low FODMAP diet is NOT an elimination diet and you are not meant to only eat low FODMAP foods for the rest of your life! The end goal of this diet is ultimately to figure out what is specifically triggering your IBS symptoms while continuing to maintain a varied and nonrestrictive diet.


    If you’re struggling to improve your IBS symptoms and wanting to start a Low FODMAP diet, don’t hesitate to seek the help of our registered dietitian. With our expertise and guidance, you can create a personalized nutrition plan that works for you and achieve your health goals. Contact us today to take the first step towards a healthier you.