What Is A Low FODMAP Diet and How Does It Help IBS?

Medically reviewed by Linda Said, MS, RD, LDN
2020-07-24

Let’s be honest, irritable bowel syndrome (IBS) is not an easy topic to bring up, especially when symptoms include flares of abdominal cramps, uncontrollable gassiness and bouts of diarrhea. Many people don’t even want to talk about it with their doctor.

The awkwardness of explaining your condition could lead to feelings of isolation, as well as physical limitations such as being afraid of going to work, always feeling like you need to be near a restroom, fear of social events or even traveling short distances because of symptoms! I know many individuals who have had to put up with daily gut issues which becomes very inconvenient, and leads to even more frustration. 

There is an option for IBS management: a low FODMAP diet. Like IBS itself, low FODMAP diets are infrequently mentioned. It’s worth demystifying though, since it can provide help. First though, some background on IBS.

What Is IBS?

In simple terms, IBS is a functional GI disorder which means that it interferes with the way the gut works or functions.  The National Institutes of Health (NIH) defines IBS as a chronic disorder that is characterized by "a group of symptoms that occur together, including repeated pain in your abdomen and changes in your bowel movements, which may be diarrhea, constipation, or both”. 

There are 3 different types of IBS and they are based on a group of symptoms or a pattern of changes in your bowel movements. IBS is classified as:

  • IBS with constipation - abdominal pain with lumpy or difficult to pass stools on days with abnormal bowel movements

  • IBS with diarrhea - abdominal pain with loose or watery stools on days with abnormal bowel movements

  • IBS with mixed bowel habits - abdominal pain with alternating loose/watery and lumpy stools

According to the American College of Gastroenterology, IBS is the most prevalent of the functional gastrointestinal disorders. Current estimates are that IBS affects up to 10–12% of adults in North America. Although it can affect all individuals, it appears that IBS is 2 times more common in women than in men, and is most commonly diagnosed in people under the age of 50. About 40% of people with IBS have mild symptoms, 35% experience moderate symptoms, and 25% experience severe IBS. 

How IBS Is Commonly Treated

It's important to know that in reality, there is no magic cure for IBS and there is no one size fits all approach. IBS is complicated! And to make it harder, the perfect solution is not in pills and tests that are commonly not backed up by scientific research.

The reality is, that finding your way to IBS freedom is not a linear process. There are going to be ups and downs and you will notice daily variations which are completely normal. Finding long-term IBS relief is a journey that requires a personalized approach. The management of IBS revolves around an integrative approach which includes but is not limited to diet, stress management, and supplements and medicines. 

A Low FODMAP Diet

A common treatment approach for IBS is examining the foods we eat, as what goes “in” is often thought to be a trigger of what goes “out”.  Different dietary changes affect people differently. What works for one may not work for someone else. Our bodies are different, so naturally our bodies’ responses are different too.

Despite this, there are some common triggers that have been identified. They are known as FODMAPs (dietary sugars known as fermentable oligosaccharides, disaccharides, monosaccharides, and polyols). These foods have been studied and can exacerbate IBS-related symptoms by providing fuel for certain bacteria in the gastrointestinal system. This is why the feeling of abdominal pain, bloating, diarrhea, and constipation occurs.

A diet that avoids “FODMAPs” is known as a low FODMAP diet. Because research groups from all over the world have shown improvement in IBS symptoms, the low FODMAP diet is now recommended as a first dietary treatment choice for people diagnosed with IBS. 

Check out this quick guide that differentiates between the high and low FODMAP foods. 

How A Low FODMAP Diet Works

A low FODMAP diet is a type of elimination diet, and is not a permanently restricted diet. You will start off with avoiding foods that contain FODMAPs. This means that at the start, your diet may change a lot, if you have previously been eating high FODMAP foods. In time, those foods get slowly reintroduced. 

The time for avoiding FODMAPs varies for different people, but the time should be long enough for it to be apparent whether the low FODMAP is helping with your IBS symptoms. It can be as short as 1-2 weeks when you start to notice improvement in symptoms; for others, it may take a few weeks longer. 

Once you start feeling better, it’s time to start the “food challenge” where you slowly start adding high FODMAP foods back to your diet. This will help identify which foods are your trigger foods. Since this whole process can be slightly overwhelming, it is highly encouraged to work with a dietician to help guide you step by step and tailor your diet based on your needs. 

Click below for our integrative approach that can help reduce and manage your IBS-related symptoms.