What are FODMAPs?

This strange sounding acronym stands for Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols. In short: fermentable sugars. While these short-chain sugars are typically grouped together, each one is found individually in certain foods.

• Oligosaccharides: These include fructans and galacto-oligosaccharides (GOS), found in foods like wheat, rye, onions, garlic, legumes, and certain fruits.
• Disaccharides: Lactose, a common disaccharide found in dairy products like milk, yogurt, and soft cheeses, falls under this category.
• Monosaccharides: Fructose, a type of sugar present in honey, many fruits, and high-fructose corn syrup, is the primary monosaccharide.
• Polyols: These sugar alcohols include sorbitol, mannitol, xylitol, and maltitol, often found in some fruits like apples, pears, stone fruits, and artificial sweeteners.

FODMAPs are not fully digested in your gut, which can cause them to be excessively fermented by your gut bacteria. When this happens the fermentation releases hydrogen gas, leading to distension of the intestines and a range of uncomfortable IBS-related symptoms, including:

• Stomach pains
• Gas
• Bloating
• Constipation
• Diarrhea

This is considered a FODMAP intolerance, and tends to be related to functional issues like small intestinal bacterial overgrowth (SIBO).

How to diagnose a FODMAP intolerance

There is no single test to diagnose a FODMAP intolerance however, people with SIBO and other chronic gut problems like IBS are more likely to have trouble with FODMAPs. Since functional medicine understands that food intolerances are often a result of underlying gut dysfunction problems like these, I like to run specific gut health labs to get a better understanding of the driving force behind your FODMAP intolerance and how to best address healing. Here are the just a few of the labs that I run for patients at my telehealth functional medicine clinic:

• Microbiome labs: This will show you whether or not you have a bacterial imbalance and if you need to boost your good bacteria. Research has shown that imbalances can dysregulate the immune system and contribute to food intolerance.
• Small intestinal bacterial overgrowth: SIBO occurs when bacteria overgrows up from the large intestines into the small intestines. This bacteria ends up eating the foods you eat and will ferment in the wrong area leading to gas, bloating, and if untreated, leaky gut syndrome.
• Leaky gut labs: These blood tests will measure antibody levels to show if there has been damage to the gut lining.
• Zonulin and occludin: These two proteins control gut permeability. Antibodies indicate damage to intestinal tight junctions.
• Actomyosin: This shows if there has been destruction of gut lining.
• Lipopolysaccharides: Antibodies to these bacterial endotoxins in your gut can indicate leaky gut syndrome.

If your results indicate that there is some gut dysfunction going on, the next step to determine for sure whether or not FODMAPs are an issue for you is to go on a low-FODMAP diet. This is the gold-standard when it comes to identifying FODMAP intolerances.

What is a Low-FODMAP diet?

A low-FODMAP diet is a three-step process that involves the elimination of high-FODMAP foods and includes a reintroduction phase.

1. Elimination phase

During this initial phase, high-FODMAP foods such as certain fruits, vegetables, grains, dairy products, sweeteners, and legumes are eliminated from your diet. Instead, you’ll opt for low-FODMAP alternatives. This can last anywhere between 2-6 weeks depending on your specific health case.

2. Reintroduction phase

Once your symptoms have subsided, it is time to move on to the reintroduction phase. During this phase, high-FODMAP foods are gradually reintroduced to help you identify the specific FODMAP foods that trigger your symptoms. By reintroducing high-FODMAP foods one at a time in small amounts, you’ll be able to better monitor your body’s reaction to each food.

3. Personalization phase

Based on your reactions during the reintroduction phase, you’ll be able to personalize a long-term diet plan. Since you now understand what foods your body loves and which ones cause a reaction, you’ll be able to eat with confidence knowing what high-FODMAP foods are ok for you to consume (if any) and how much you can have in one sitting.

It’s important to note that for some people, the elimination phase will have to be a lot longer than the suggested 2-6 weeks. As I mentioned earlier, since food intolerances are often caused by gut dysfunction, it can take much longer (anywhere between 12-24 months) to see sustainable healing from these gut problems and before you may be able to introduce more moderate to high-FODMAP foods into your diet.

This is why it is so important to simultaneously work on healing your gut during the elimination phase of this diet with probiotics, soothing food medicines, and other healing tools. You can eliminate foods all you want, but if you aren’t addressing the source of your FODMAP intolerance, you’ll never even get the chance to reintroduce certain FODMAP foods with success.