Recent research found up to 86 percent of people with IBS saw improvements in their symptoms while on a low FODMAP diet. But the Low FODMAP Diet has not only been shown to help many people with IBS, but may also be helpful for other gut conditions such as coeliac disease, Crohn's and Colitis.
Well, the low FODMAP diet works, in part, by starving your gut bacteria4. For a short period, this can help bring your system back into balance. However, in the long-term, this likely isn't a very good idea because a healthy gut flora is important for digestive health, nervous system health and immune function.
Most FODMAP-trained dietitians have reported it takes an average of 2-4 weeks to see noticable changes. But at the end of the day, it depends on your body. Some people have reported seeing changes in the first few days, while others see a shift right at the 4-week mark.
The short answer is no. In fact, we do not encourage patients with Irritable Bowel Syndrome who have been following a low FODMAP diet to continue the diet in the long term. This is for a number of reasons: 1.
There is also concern that long-term restriction of high-FODMAP foods changes the makeup of bacterial colonies in the gut, which may negatively impact intestinal health and possibly worsen digestive issues over time. Oligosaccharides, in particular, are an important energy source for beneficial bacteria.
Following a low fodmap and other restrictive diets can increase the anxiety and stress you feel around meal times in general, and when it comes to eating certain foods. Unfortunately, you start becoming afraid of food and fearful of reintroducing them back in, due to what may happen with your symptoms.
We recommend staying on the diet for at least 3-4 weeks as it will take about that long to “heal the gut.” Some patients may take up to 3 months to reestablish a normal functioning intestinal mucosa. In my experience, everyone who goes through this process feels better in the end.
You may also be eating more starches and sugars from hyper-processed gluten free, low FODMAP packaged foods than usual, which may overwhelm the absorption capacity of a sensitive, hyper-active gut. If you suspect this, try eating more fruits, vegetables, nuts and seeds and see how you feel.
FODMAP Disadvantages
Low-FODMAP diets have some drawbacks, such as being unable to eat readymade or processed foods which do not list the ingredients in detail, or may contain FODMAPs but in too low quantities to be of clinical significance.
“We recommend following the elimination portion of the diet for only two to six weeks,” says Veloso.
You can assess your symptom response to a low FODMAP diet using the food and symptom diary in the Monash University low FODMAP App™. This diary allows you to track changes in your IBS symptoms as you follow the diet. Alternatively, you can rate the improvement in your IBS symptoms on a simple, 0 to 100 scale.
“For patients who have a lot of bloating, gas, heartburn or diarrhea, following a low FODMAP diet may reduce inflammation by reducing fuel for more problematic bacteria. This can have a calming effect in the gastrointestinal tract and may help reduce inflammation in other areas, including joints,” she says.
The low FODMAP diet deprives beneficial bacteria (such as Faecalibacterium, Roseburia, Bifidobacterium, Akkermansia, Lactobacillus and others) of the food they like to eat, and these species wane (see here).
The 4R program offers four steps—remove, replace, reinoculate, and repair—that can address the underlying causes and restore balance, helping to alleviate symptoms. Depending on the severity of your condition, it can take up to six months to fully repair your gut.
An anti-inflammatory diet, regular exercise, good quality sleep, and probiotics are all strategies to put in place before trying antimicrobials or antibiotics to get rid of bad bacteria.
Glutamine is the substance your gut naturally uses to repair intestinal cells. Supplementation with L-glutamine can help speed the repair of the intestinal lining, decrease intestinal permeability, and reduce inflammation.
Fasting during prolonged periods gives the gut the time it needs to restore its integrity. This is especially important for those with “leaky gut”, also called intestinal permeability, where the gut lining is weakened thereby allowing toxins, partially digested foods and pathogens to enter the bloodstream.
Can I have a cheat day while on the low FODMAP diet? The good news is that cheating with high FODMAP foods will not damage your body but they might make you feel rotten.
One reason the low-FODMAP diet may not work is that you may not have IBS but actually have another disorder. Your healthcare provider may need to do more tests, or you may need to go to a specialist. Other possible diagnoses include: Inflammatory bowel disease.
Some people might find relief in a few days; others can take a couple of weeks. So, if your symptoms persist, it's time to start troubleshooting so you can decide if you want to continue with the FODMAP diet or move on to a different strategy.