The categories

The term FODMAP was coined to give a name to 4 categories of short-chain carbohydrates which all irritate the gut, one way or another. These are:

1. Oligosaccharides;
2. Disaccharides;
3. Monosaccharides;
4. Polyols

Two of these four categories are umbrella terms: oligosaccharides and polyols. In total there are six types of short-chain carbohydrates that irritate the gut, causing the symptoms named above. These categories are:

• Fructose;
• Lactose;
• Galactoligosaccharides;
• Fructans;
• Sorbitol;
• Mannitol.

Fructose is a monosaccharide.

Lactose is a disaccharide.

Both galactoligosaccharides and fructans are oligosaccharides.

Both sorbitol and mannitol are polyols.

The four categories – below on the left – are important to remember, because together they form the name of this diet: FODMAP.

However, the six categories – below on the right – are even more important to remember, because these categories are the ones we will be referring to most often, as these are the six categories that cause your symptoms.

The reason why all of these complicated names and categories are important to know, is because one might get symptoms from all polyols, but one might also only get symptoms from one of the polyols.

For example, when you only get symptoms from mannitol and not from sorbitol, there would be no need to cut out all polyols from your diet. In that scenario, it would be better to only cut out mannitol.

But how do you know which FODMAP’s you do tolerate and which FODMAP’s you don’t tolerate? Well, that’s what the phases of the low-FODMAP diet are for.

The phases

The low-FODMAP diet consists of 3 phases:

1. The low-FODMAP phase
During this phase you only consume low-FODMAP foods.

This phase is temporary and meant to stabilize your symptoms, in preparation for reintroduction.

2. The reintroduction phase
During this phase you test each of the 6 FODMAP’s (fructose, lactose, fructans, galactoligosaccharides, sorbitol and mannitol) one-by-one. Over the course of three days, you gradually increase the portion size of the FODMAP you consume – to figure out which FODMAP’s do give you symptoms and which don’t.

3. The personalization phase
During this phase you reintroduce the foods you do tolerate, while leaving out the foods you don’t tolerate. Finding your new balance! This means the personalization phase will result in different diet restrictions for different individuals – depending entirely on your personal tolerance to the six FODMAP’s.

Concluding

FODMAP’s are short-chain carbohydrates that irritate the gut one way or another.

During the first phase of the low-FODMAP diet, you restrict the intake of any and all FODMAP’s.

During the reintroduction phase of the low-FODMAP diet, you learn which FODMAP’s you do and do not tolerate.

During the personalization phase, you figure out a way of eating which integrates the FOMDAP’s you tolerate, while avoiding those you don’t – in order to restricts as little food as possible, while steering clear of that which causes you  symptoms.

It’s important to remember that the low-FODMAP diet is not permanent and unlike the term diet might suggest, this is not a diet which aims for weight loss. The low-FODMAP diet is a medically induced diet, that should only be started after a doctor advised you to do so and should only be followed under close supervision of a medical professional.