About Fructans & Galacto-oligosaccharides (GOS)

What are Fructans & Galacto-oligosaccharides (GOS)?

This month is Irritable Bowel Syndrome (IBS) Awareness Month and we are doing a deep dive into each FODMAP sugar group! We will begin with the “O” in “FODMAPs” which stands for  Oligosaccharides. The “O” in FODMAPs specifically refers to the two types of oligosaccharides – fructans and GOS.

FODMAPs are short chain carbohydrates that naturally occur in some vegetables, fruits, cereals and legumes. Some examples of foods that are high in fructans and/or GOS are garlic, onion, wheat and beans.

Why do some people have issues with fructans and GOS?

Our small intestines lack the enzyme required to breakdown oligosaccharides and therefore are not absorbed. Fructans and GOS pass through to the large intestine where they are fermented by gut bacteria, producing gases in the process. People with IBS tend to have heightened visceral hypersensitivity, which means they tend to have an enhanced perception of pain and discomfort triggered in the bowel. Therefore, when excess gas is produced in the large intestine by fermentation of oligosaccharides, people with IBS tend to experience symptoms like painful cramping and bloating, whereas those without IBS, do not experience abdominal discomfort after consuming oligosaccharides.

What nutrients are at risk for those who avoid foods high in fructans and GOS?

Fructans and GOS are prebiotics. Therefore, eliminating fructans and GOS from your diet can lead to insufficient prebiotic fibre intake. Prebiotics feed the bacteria in your large intestine and promote long-term gut health.  It is important to consult a dietitian before eliminating oligosaccharides from your diet to avoid unnecessary food exclusions including prebiotic foods. Your dietitian can also advise on some low FODMAP prebiotic foods to substitute into your diet if you have to avoid oligosaccharides to manage your IBS symptoms.

What are common foods that are high in fructans and GOS? What are their substitutes?

FODMAP Friendly Certified Products

To make it easier for you when following a low FODMAP diet, there are a wide range of FODMAP Friendly certified products that can be consumed safely, including breads, pasta, sauces, snacks, beverages, desserts and more. When consuming the suggested serving size, these products are not only low in fructans and GOS, but are also low in all other FODMAPs too. Visit https://fodmapfriendly.com/certified-products/ to see more.

Stay tuned for our daily posts over IBS Awareness Month! We will have more informative articles like this one including low FODMAP recipes, myth busting and more!