Why low fodmap not working?

Why The Low-FODMAP Diet Might Not Be Working For You

So you’ve discovered the low-FODMAP diet, and it seems like the answer to your prayers, but after several weeks of avoiding FODMAPs you’re still feeling rubbish and your IBS symptoms haven’t gone away…

Well, this is a common problem and there’s a few reasons why this might be happening. Below, I’ve outlined some of the biggest, non-FODMAP related causes of IBS and other digestive problems so you can identify the issues and make the necessary changes to your diet to improve your digestive health.


The low-FODMAP diet prohibits wheat and rye with other grains, such as oats, rice, corn and buckwheat, being suggested as substitutes. However, these grains can also cause digestive problems for some. This is because, although gluten-free, they still contain a similar proteins that break down the microvilli in your small intestine over time. Not to mention the abnormal spikes in insulin that most grains cause too.

So, if you’re heavily substituting your wheaty treats with other grainy goodies, then it may be time to reconsider.


Sweeteners such as sorbitol and xylitol are high in FODMAPs, but normal sugar isn’t. This can mean desserts, cakes, biscuits and other sweets (all wheat-free of course) can often become common treats for those on a low-FODMAP diet. This is particularly true if the low-FODMAP diet feels very restrictive and you want to treat yourself to make up for the lack of choice at meal times.

Unfortunately sugar is a big cause of digestive issues, such as bloating, gas and even more severe conditions such as leaky gut syndrome. If you’re still experiencing IBS symptoms after following the low-FODMAP diet, cutting back on sugar is a good place to start.


Lactose is one of the big no-nos in the low-FODMAP diet, but the general advice is that some cheeses and dairy products contain such a small amount of lactose that they can be deemed safe. This includes cheeses like brie, camembert and parmesan as well as butter. However, some people (me included) find that even the tiniest amount of lactose can have disastrous effects and trigger severe IBS symptoms.

If you are still consuming cheese or butter, it may be worth removing these from your diet for a couple of weeks, to see if it makes any difference.

Not Following the Rules

If you don’t think any of the above apply to you, maybe you just haven’t been as strict as you could have been when following the elimination and reintroduction process? If you’ve forgotten the rules, or you just dived straight into the diet without ever following a plan a detailed guide to the various stages of low-FODMAP diet can be found here.

The key is to make sure your elimination phase is as clean as possible, and you only introduce high-FODMAP foods back into your diet one by one. This is to ensure you know exactly what is causing you problems. If you accidentally consume anything high in FODMAPs during either phase, you must eliminate all FODMAPs for another week before reintroducing anything.

The above are just a few of the things which could be negatively affecting the success of your low-FODMAP diet. I have personally found that grains are an issue for me as well as lactose, but everyone is different so please listen to your body and your healthcare professional above all else.

Have you struggled or are struggling with the low-FODMAP diet? Let me know in the comments.

***Note: I’m not a doctor or dietician. Please seek professional help if your IBS symptoms persist after following the low-FODMAP diet and please don’t take this post as dietary or medical advice.***

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