Low-FODMAP diets: are they safe in the long-term?

Yes, the low-FODMAP diet works.

There are now plenty of studies and cases of people with various digestive conditions, including

  • IBS (irritable bowel syndrome),
  • IBD (inflammatory bowel disorders like Crohn’s disease or ulcerative colitis),
  • celiac disease,
  • fructose malabsorption and
  • SIBO (small intestinal bacterial overgrowth).

If you want more information about the low-FODMAP diet and how it can help your digestive symptoms, read this. You can also get my Paleo low-FODMAP food list here.

fodmap safety

What are FODMAPs again?

FODMAPs are a group of fermentable short-chain carbohydrates that can act as food for the bacteria in the gut. In other words, FODMAPs are prebiotics.

Don’t be confused with the words probiotics and prebiotics.

  • PRObiotics mean pro-life and correspond to live beneficial bacteria that you can take either:
    • in the form of supplements
    • from traditionally fermented foods (sauerkraut, kimchi, yogurt, kefir, kombucha)
  • PREbiotics refer to what comes before life or, in other words, what is needed to feed life.
    They are found:

    • in various plant foods (the parts we usually cannot digest, such as fibers and FODMAPs)
    • in some supplements on their own or combined with probiotics (inulin, fructo-oligosaccharides or FOS, chicory root, etc).

Wouldn’t FODMAPs be a good thing then?

Sounds like prebiotics are a good thing if they feed your gut flora, doesn’t it? Absolutely!

Well they are but there is a big IF. FODMAPs are very beneficial for your gut flora:

  • IF you have a healthy gut flora to begin with and
  • IF you don’t have a bacterial overgrowth in your small intestines (SIBO).

The thing is that FODMAPs tend to feed the good bacteria living in your gut but it can also feed them too much. Or if you have too much bacteria in the wrong place, as is the case with SIBO, the fermentation resulting from feeding FODMAPs to these bacteria who are not where they should be, can cause many digestive issues such as:

  • bloating and distension,
  • constipation,
  • diarrhea,
  • abdominal discomfort, pain or cramping,
  • flatulence,
  • belching, etc.

This is why the low-FODMAP diet can often really help people suffering from any of the above digestive symptoms find a way to control them. By stopping feeding the wrong kind of bacteria or the excessive amount of bacteria present in the wrong part of your gut, the low-FODMAP diet is definitely effective at keeping these bacteria in check and allowing you to have a more normal time in the bathroom and elsewhere. 😉

Is the low-FODMAP diet safe in the long-term?

I won’t be discussing about the nutritional adequacy of the low-FODMAP diet because I’ve already shown that it can be perfectly adequate, especially if based on REAL food as I explain in my book Digestive Health with REAL Food.

What today’s post is about is the long-term safety of depriving your gut flora
of naturally-occurring prebiotics in the form of FODMAPs.

Prebiotics like FODMAPs are an important part of a healthy and balanced diet if you want to keep your gut flora healthy and balanced as well.

The science: low-FODMAP diets and your gut flora

A cross-over study published in the January 2015 issue of the scientific journal Gut titled “Diets that differ in their FODMAP content alter the colonic luminal microenvironment” showed that the FODMAP content of the diet can have marked effects on the composition of the gut flora.

In their study, a group of 26 subjects with IBS and 6 healthy subjects followed two diets for 21 days each with a washout period (regular diet) in between. The diets only differed as far as their FODMAP content, which was low in one diet (3 g per day) vs high in the other (17-31 g per day). And the scientists then looked at their poop at various times.

The DNA stool analysis showed that as little as 3 weeks of liming their FODMAP consumption caused a dramatic shift in the gut flora by decreasing total bacterial abundance (by an average of 47%). On the other hand, eating a high-FODMAP diet rich in vegetables, fruits and tubers seemed to stimulate the growth of beneficial gut bacteria.

What does that mean?

We know that your gut flora is not only important for your digestive health but also for your health beyond the gut. Studies have shown associations between the gut flora and autoimmunity, obesity, type 2 diabetes, cardiovascular diseases, Alzheimer’s disease, liver disease and many more other chronic diseases of today.

The low-FODMAP diet is a great tool to help you control your digestive symptoms
in the short-term but it doesn’t address the root cause of your problem

Sometimes you have to simply avoid foods you are sensitive to, such as gluten or casein, because the root case cannot always be corrected. But I firmly believe that an intolerance to FODMAP is not like any other type of food sensitivities stemming from a leaky gut, inflammation or damages to the gut. From my personal and professional experience and from understanding the pathophysiology of fructose malabsorption and FODMAP intolerance, I believe it is caused by an imbalance in the gut flora.

And the good news is that if you fix your gut flora,
you should be able to tolerate FODMAPs again.

It is certainly my case. And I’ve seen many of my clients being able to do the same too. 😉
There’s hope!

What should I do if I need to eat low-FODMAP
to control my digestive symptoms?

You need to find the root cause of your FODMAP intolerance! I know, easier said than done.
Keep reading for ideas on how to do this.

1. make sure you find the root cause of your digestive issues

If you react to FODMAPs, you most likely have some form of gut dysbiosis (imbalance in your gut flora) in your colon. Or you have an overgrowth of bacteria in your small intestines (SIBO). I don’t usually recommend taking the breath test for fructose, lactose or sorbitol because you can easily figure out if you are intolerant to FODMAP simply by following a low-FODMAP diet (if your symptoms improve, you have it).

But it might be very useful to get tested for SIBO (work with a functional or naturopathic doctor to get the test and make sure it measures both hydrogen and methane levels). SIBO is actually a very common cause of FODMAP intolerance and can be treated (with antibiotics or herbal antimicrobials), although the root cause of SIBO also needs to be treated to prevent recurrence but that would be the topic for another post.

You should also ensure you don’t have any chronic gut infections (think parasites or candida for example), low stomach acid, an inflamed gut and/or a leaky gut, as these could all be part of the vicious cycle contributing to and resulting from gut dysbiosis.

2. rebuild a healthy gut flora

It is primordial that you work on rebuilding your gut flora. You can first follow the low-FODMAP diet for a month or so to calm your digestive symptoms and allow the damage to your gut lining to heal and the inflammation in your intestines to subside.

Your low-FODMAP diet should also include anti-inflammatory, nutrient-dense, and healing foods (i.e. homemade bone broth) as suggested in the Digestive Health with REAL Food protocol to heal your gut and help your gastrointestinal tract digest and absorb nutrients more efficiently.

But once you start feeling better (while trying to fix the root cause of your FODMAP intolerance as discussed above), it’s really important that you start implementing a combination of the strategies below to balance your gut flora to ensure it is healthy and diversified and allow you to tolerate FODMAP foods again.

a) add probiotics

Probiotics can be very beneficial in making your gut a healthier environment and in promoting its colonization by gut-friendly bacteria. You can get your probiotics either from supplements or fermented foods. Both have pros and cons. Here are a few things for you and your health care provider to consider to help you choose the best option for you.

Probiotic supplements
* A selected number of strains (from only 1 to up to a dozen)
* Ability to control the dose (easier to determine how much beneficial bacteria,
measured in CFU, you’re taking in)
* Variable quality (choose a trusted brand!)
* Other ingredients in the supplements might be problematic for some
* More expensive but also more convenient

Natural probiotics (fermented foods)
* Wider variety of strains
* More difficult to control the dose
* Comes with natural prebiotics (food for these probiotics)
* More time-consuming preparation but cheaper
* Tasty and nutritious as a bonus!

FF_300x250Learn how to make your fermented foods with my friend Sarah:
* sauerkraut
* water kefir
* fermented veggies
* kombucha
Whichever you choose, just make sure you introduce probiotics in a slow and gradual manner to assess your tolerance and gently balance your gut flora (as opposed to causing a quick and large shift which could be uncomfortable if you have a sensitive tummy).

b) reintroduce FODMAPs slowly and gradually

The low-FODMAP diet was never meant to be a permanent diet like a gluten-free diet should be (at least for people with celiac disease or gluten intolerance).

The goal of the low-FODMAP diet is the same as any other elimination diet:
reset your digestive system so you can go back to a more comfortable baseline to work from.

Once you have been on the low-FODMAP diet for 3-6 weeks, it’s time to reintroduce FODMAP-containing foods slowly and gradually to assess your tolerance to each one of these. I describe the best fail-proof method to do that in Digestive Health with REAL Food (reintroduction phase of the elimination diet protocol).

You should be able to tolerate at least some FODMAP-containing foods.

Maybe not all of them.

Maybe not in large servings at first.

And many not all the FODMAP foods you can think of on the same day.

What matters is that slowly but surely, your diet should become more varied and enjoyable as you heal your gut and balance your gut flora by following the above steps.

c) consider resistant starches

A last step that might be beneficial to feed and balance your gut flora might be the use of resistant starch. It can be done in concert with the other strategies above to improve the health and diversity of your gut flora, whether it is using probiotics or adding FODMAP foods to your diet, or as an alternative if either one of these methods isn’t working for you.

I’ll discuss resistant starch more in a future post but you can start researching this option.

Potato starch (unmodified) is probably the easiest (and most concentrated) source you can find. Again, with anything that can affect your gut flora, even positively, make sure you introduce it slowly and gradually to avoid unpleasant side effects that can be associated with a rapid and major shift. For example, you can start with only 1/4 to 1/2 of a teaspoon (1 ml) and slowly build your way up to 2 to 3 tablespoons (30-45 ml) a day.


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What do YOU think?

Have you been able to reintroduce FODMAPs?

If you need help, check out my Radicata Nutrition Package here.