What the FOD? The Low FODMAP Diet Explained

THE LOW FODMAP DIET


Jenelle Croatto APD

For many years, gluten, wheat, dairy and an array of other foods have been blamed as a cause of Irritable Bowel Syndrome (IBS).  While many sufferers of IBS have reported an improvement in symptoms after excluding such foods, many find that IBS symptoms continue to lurk and that it can be a challenge to pinpoint what food is really to blame.

Fortunately, recent research into food and IBS has found that a group of poorly absorbed dietary sugars known as “FODMAPs” may be a contributing factor to the dreaded ‘bloat’ and other digestive issues such as changes in bowel habits (diarrhoea and/or constipation), excessive wind and abdominal pain.

What Are FODMAPS?

FODMAPs are an acronym, which refers to

Fermentable

Oligosaccharides (e.g. Fructans and Galacto-oligosaccharides (GOS))

Disaccaharides (e.g. Lactose)

Monosaccharides (e.g. Excess fructose)

And

Polyols (e.g. Sorbitol, Mannitol, Maltitol, Xylitol and Isomalt)

FODMAPs are naturally found in the food we eat and may cause symptoms in some people.  As FODMAPs are quite small in size, malabsorption of these sugars can lead to diarrhoea.  As these sugars travel through to the large intestine healthy gut bacteria will start the natural fermentation process and may cause wind, bloating, abdominal pain and discomfort.  For some, this accumulation of gas in the bowel actually slows down bowel movement and results in constipation.

Interestingly, FODMAPs are poorly absorbed in all people, however there are two main reasons why those with IBS may have a lowered tolerance.

1.    Gut hypersensitivity to gas production – some individuals produce a greater amount of gas in the large intestine, or may be more sensitive to the gas which is produced.

2.    Bacterial overgrowth in the small intestine – healthy gut bacteria, which are naturally located in the large intestine, may move up into the small intestine resulting in Small Intestinal Bacterial Overgrowth (SIBG).  As the small intestine is narrower than the large intestine, significant discomfort may be felt when gas is produced is this section of the bowel.

Should I follow a low FODMAP diet?

Persistent gut symptoms should always first be explored by a medical practitioner so other medical conditions can be ruled out.  If your medical practitioner gives the all clear and only suspects IBS then a trial of the low FODMAP diet will be recommended.

What can I eat on the low FODMAP diet

The good news is that the low FODMAP needn’t be followed for life.  The diet is simply a test diet to help bring symptom relief and is carried out in two phases.  The first phase involves a restriction of all high FODMAPs foods for a period for 6-8 weeks, although some people may experience symptom relief earlier in this time period.  The second phase is to liberalise the diet with the help of an expert dietitian to help determine which FODMAPs are contributing to IBS symptoms.  Finally the dietitian will work with you to find a comfortable intake of higher FODMAP foods that you can happily eat without exacerbating IBS symptoms.

Having a good understanding of which foods you can and cannot tolerate can be extremely liberating! If you’re a sufferer of IBS do yourself a favour and speak with one of our expert dietitians to see if a lowered FODMAP diet can help put gut issues to rest.