Wondering what the FODMAP diet is and if it works, you’re not alone. The FODMAP has been gaining acceptance in recent years for people with IBS or other digestive problems, it can be a real lifesaver and for others it may not actually do much.

What Is the FODMAP Diet?

The FODMAP diet has gained popularity in the past few years for its ability to help alleviate symptoms for those with digestive issues. FODMAP is an acronym, that stands for Fermentable Oligo-saccharides, Di-saccharides, Mono-saccharides And Polyols. To break this down in more simple terms, FODMAPs are short chain carbohydrates found in many foods such as apples, honey, agave syrup, sugar alcohols, garlic, wheat, inulin and onion.

Current research investigating diet and irritable bowel syndrome indicates FODMAPs may contribute to Irritable bowel syndrome (IBS) symptoms in some people, as many of these foods are poorly absorbed in the small intestine and can then be fermented by bacteria to produce gas and digestive symptoms.

The aim of the FODMAP diet is to partially, or completely, eliminate FODMAPs from your diet for a period (usually 2-6 weeks) to see if these foods are contributing to your digestive symptoms. After you have completed the elimination phase and experienced a reduction in symptoms, FODMAP containing foods can slowly be reintroduced one at a time. This reintroduction phase aims to highlight any potential food triggers, so you can see which foods, if any, are causing your digestive discomfort.

What foods should be avoided on this diet?

Fermentable Oligosaccharides
There are two different groups of oligosaccharides: fructans and galactans. Fructans are found in wheat products, onions, garlic, artichokes. Galactans are found in lentils, chickpeas, and soy-based products.

The most commonly known disaccharide is lactose, which naturally occurs in milk and some dairy products and requires lactase, a digestive enzyme, for absorption. Milk, yogurt, soft cheeses, ice cream and puddings are all disaccharides containing lactose.

Fructose is a monosaccharide found in fruits. Fructose absorption is enhanced when it is combined with sources of glucose, another type of sugar. Therefore, when it comes to FODMAPs, not all fruits are equal. Those containing equal amounts of fructose and glucose may be more easily tolerated. Some examples of higher-fructose containing foods that may cause gastrointestinal symptoms include (but is not limited to) agave, honey, mangos, watermelon, sugar snap peas and high fructose corn syrup.

Polyols are sugar alcohols found in some stone fruits (such as cherries and nectarines), apples and pears; in vegetables such as mushrooms and cauliflower; and in some sugar substitutes containing xylitol or sorbitol.

*This is not an exhaustive list.

What conditions is the FODMAP diet helpful for?

The FODMAP diet may be well suited to those with Irritable Bowel Syndrome(IBS) or digestive problems. IBS is a common functional gastrointestinal disorder, characterized by gastrointestinal symptoms that are not explained by other disorders. The most common symptoms of IBS include excessive gas, bloating, altered bowel habits and lower abdominal pain.

Even those with the best digestion may not absorb FODMAP foods, however it is thought that symptoms may be more prominent in those with IBS due to factors such as gut hypersensitivity and/or bacterial overgrowth.

A side-note on IBS: It’s common for your doctor to diagnose you with IBS and tell you that you’ll just have to live with it and that there’s nothing you can do. This is not the case, I work with clients to overcome their IBS through food.

When should you use the FODMAP diet?

The FODMAP diet isn’t typically my go-to with clients initially at least. It’s more of a last resort, but it can be useful, particularly when symptoms just aren’t going away.

Prior to a FODMAP diet, I would look at food sensitivities and stress factors. If nothing resolves, then I’d look at SIBO (small intestinal bacterial overgrowth) and the FODMAP diet.

The FODMAP way of eating is not designed as a long-term diet plan. It can help individuals heal their gut, gain some control over their symptoms and investigate their potential trigger foods or intolerances, but it isn’t a diet you want to go at alone as it can be quite complex, especially with the process of elimination and reintroduction. If you want to do the FODMAP diet, research indicates it works best when those following the diet have the time and commitment to follow the program as strictly as possible.

Is the FODMAP diet a long-term solution?

This diet is ideally a short term-term diet to help you investigate whether FODMAPs are playing a role in your digestive symptoms. Since it’s so restrictive, it has the potential to limit many nutritious food groups. Often though, it’s only a few foods that actually cause issues, not every single FODMAP food.  After the reintroduction stage, if you realize there are a couple of foods that still trigger issues, you may decide to leave out those certain ones.

Some benefits of a FOMAP diet can include

  • Symptom management and understanding of potential food intolerances & triggers
  • Reduction in the consumption of refined sugars
  • Healing of the GI tract
  • Shorter time span than some therapeutic diets used for digestive symptoms (approximately 2-8 weeks elimination, followed by reintroduction phase)

Some limitations of a FOMAP diet can include

  • This diet allows some foods which may not be considered healthy, such as refined, processed foods, just because they are low FODMAP
  • Lengthy reintroduction stage
  • Requires a lot of body awareness and discipline
  • Time consuming, impacts on social life (e.g. eating out can be challenging)
  • May be challenging for vegans to get adequate nutrition, as certain foods such as most beans and legumes are restricted on the diet.

Carol Aguirre MS, RD/LDN