Are all gluten free products low FODMAP?
Don’t be fooled! Not all gluten free products are low FODMAP. Just because a product says it is gluten free that does not mean it is always safe for the low FODMAP phase of the diet. Gluten free products often lack fibre and flavour. This means manufacturers sometimes pack them full of high FODMAP ingredients to improve nutrition and make them more palatable.
Why are gluten free products recommended on the low FODMAP diet?
The low FODMAP diet is not a gluten free diet so it can be difficult to understand why gluten free products are recommended. Gluten is a type of protein found in wheat endosperm (in layman’s terms, this is the type of tissue produced in seeds that is ground to make flour) (1). Gluten protein is not a source of FODMAPs (only certain carbohydrates are FODMAPs). Gluten is commonly found in wheat, rye, and barley.
Fructans are a type of oligosaccharide and fall within the ‘O’ group in the FODMAP acronym (2). Wheat, rye and barley all contain high levels of fructans. These grains are a major source of FODMAPs in western diets.
Gluten free products are recommended on the low FODMAP diet as they remove wheat, rye and barley from our daily diets. This can significantly reduce our intake of fructans and our overall level of FODMAPs.
What are some common high FODMAP ingredients found in gluten free products?
Gluten free products often lack fibre and so to counter this, manufacturers add inulin (chicory root extract/dietary fibre), apple fibre, fructo-oligosaccharides (FOS), oligofructose, or other high FODMAP fibre sources to products, to increase their nutritional value.
To make products more palatable, manufacturers often add high FODMAP sweeteners like: honey, apple or pear juice, fruit juice concentrate, high fructose corn syrup, fructose-glucose syrup, agave syrup, fructo-oligosaccharides (FOS), oligofructose, fructose (isolated), or polyol sweeteners (sorbitol (E420), mannitol (E421), maltitol (E956), xylitol (E967), and isomalt (E953)).
Not all gluten free flours are low FODMAP either. Almond flour/meal (½ cup serve), amaranth flour, coconut flour and lupin flour are all high FODMAP (2). Soy flour, chickpea flour, besan flour, gram flour and lentil flour are all suspected to be high FODMAP although they haven’t been officially tested by Monash University.
Also watch out for high FODMAP dried fruit and lactose containing ingredients like whey protein concentrate, yoghurt, buttermilk, milk, and milk solids in gluten free products.
Please note this is not a complete list of high FODMAP ingredients that could be found in gluten free products.
How do you select low FODMAP gluten free products?
Look for gluten free products that do not contain high FODMAP ingredients. The Monash Low FODMAP app is a great tool that can help you check for high FODMAP ingredients. It is also convenient, as you can check ingredients in the supermarket using your phone app.
Can any gluten containing products be eaten on the low FODMAP diet?
Many people on the low FODMAP diet should be able to tolerate small amounts of gluten containing oligosaccharides like the small amounts of wheat in soy sauce, two wheat based biscuits, or even one slice of white bread (2)
Just remember that not all gluten free products are low FODMAP. This means you need to check the gluten free product ingredient lists carefully to make sure high FODMAP ingredients are not sneaking into your diet.