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  • Writer's picturefranceswalker@thefoodinto

How long does it take for FODMAPs to leave your system?

Updated: Apr 8

The brilliant thing about FODMAPs is that unlike some other Food Intolerances, reducing FODMAPs in your diet brings about a pretty quick change.

If you are FODMAP sensitive, then only a few days to a week can stand between where you are at now and how you could be after reducing the FODMAPs in your diet.

The trick here is in removing all the significant sources of the FODMAPs in your diet.

Doing this diet with a Food Intolerance Dietitian used to working in FODMAPs and Food Intolerances will help you get there so much faster, as significant sources of FODMAPs can be easily identified, and short cuts to the diet implementation may be obvious based on your unique reaction profile.

Why FODMAPs leave your system quickly

FODMAPS are little carbohydrates that are not fully absorbed across the gut wall so stay in the gut and after 4 hours to 24 hours (on average) reach the large intestine.

FODMAPs attract water into the gut, on reaching the large intestine = lots of food for our gut microbes. This means heaps of gas is produced as the microbes rapidly ferment and devour the FODMAPs from the food and drink you consumed.

Over sensitive nerve endings/receptors pick up on this this extra water/ gasses/volume in the gut and via the gut-brain axis, this information is translated as pain, and you get all or some of the different FODMAP issues: gut bloat, gut pain, loose stools or constipation or both, excess gas and other symptoms that hinge on the changed gut scenario: reflux, fatigue and even sometimes bladder irritability due to the proximity of the gut and bladder nervous system.

This FODMAP reaction in the large intestine then subsides as the undigested contents move out the large intestine and exit the body!

So- the FODMAP symptoms only last as long as the large intestine gut fermentation is occurring, and once the FODMAPs move into the rectum and then passed out of the body, they can't cause issues any more.

That is why relief can be quick- as long as the food exits the intestine (as poop) and not being topped up with fresh FODMAPs in your food- you can get some very quick results.

Sometimes it takes a little longer for a very sensitive gut to recover but for many people, recovery is quite rapid.

Ongoing issues points to the possibility of FODMAPs still being in the diet, which can be checked by a Food Intolerance Dietitian.

You don't need to be on the Low FODMAP diet very long

As FODMAPs leave the gut system quite quickly, it means that a Low FODMAP diet can quickly improve or even resolve gut symptoms, if you are FODMAP sensitive.

Some people may have resolved or significantly improved symptoms after 2-5 days of reducing the FODMAPs in the diet.

The general recommendation is for 2-6 weeks on the Low FODMAP diet, but as soon as you think you have your symptoms better controlled- you are ready for the next phase of the low FODMAP diet: finding your FODMAP triggers via easy food trials. This may start 10 days or 2 weeks after first starting the Low FODMAP diet.

It is not wise to stay on the Low FODMAP diet longer than necessary, as we may be intact eliminating some FODMAP groups that are not a problem, and keep in mind that FODMAPs are actually healthy for our gut.

How long does it take to recover when you accidentally eat FODMAPs

Not long. Maybe just 2-3 days. As long as it takes for the FODMAP offending food or drink to move through your gut and for your irritated gut to calm down.

Take some first aid steps to help calm your gut:

  • Peppermint oil found in normal peppermint tea or over the counter preparations such as MIntec can help the smooth muscles in the gut to calm down and stop cramping

  • Buscopan can help with gut cramping

  • Heat packs to sooth a sad gut

  • Gentle movement as tolerated to help the gut contents to move through the gut

As I tell my clients- we can see very quickly if FODMAPs is your issue. Trial a low FODMAP diet (thinks of it as a Medical Test), have all your significant FODMAP sources identified, do the diet more easily and efficiently with a FODMAP and Intolerance Trained Dietitian. Move quickly onto food trials and finding your actual triggers and expand your eating plan for easier living while managing your gut symptoms.

Updated 8/4/24


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