The Lowdown on the Low-FODMAP Diet (2024)

By Lynne Lalor

Through the rise of social media, it’s never been easier to find a new elimination diet to try. With all of them swearing to solve your problems, trying to find “the right one” can feel like doing a word search with no word bank. One diet you might have come across is the low-FODMAP diet. With promises of soothing gastrointestinal (GI) distress, you may have asked “is this right for me?”. Maybe! But not so fast—let’s look at the fine print before deciding.

First, what are FODMAPs?

FODMAP stands for Fermentable Oligosaccharides Disaccharides Monosaccharides and Polyols. These are nondigestible, short-chain, carbohydrates that pull water into the GI tract as they pass through, increasing the volume of the intestines. Bacteria that live in the GI tract also easily ferment these carbohydrates, creating gas and causing an increase in volume. For most people, these normal processes don’t cause issues. For those with irritable bowel syndrome (IBS), the expansion of the stomach from the water and air may cause distress on their more sensitive GI systems, leading to the common symptoms of IBS like abdominal pain, excessive gas, diarrhea, and bloating. Some examples of high FODMAP foods include: honey, mango, wheat, milk, garlic, onion, and beans.

What is the low-FODMAP diet?

The low-FODMAP diet is a type of elimination diet where foods that are high in FODMAPs are first completely removed from the diet (the elimination phase), and then slowly added back in (the reintroduction phase). The goal of this diet is to find “trigger food(s)” or the food(s) that cause the most frequent and severe problems. High FODMAP foods aren’t automatically problematic for all people with GI issues; sensitivity varies from person to person. The low-FODMAP diet is intended to find some clarity on what food(s) may be causing problems for that person. In other words, just because garlic is high in FODMAPs doesn’t mean it’s a trigger food for everyone with IBS. Also, the amount of the FODMAP-containing food plays a role in symptoms. Many people can continue to eat certain FODMAP foods in small amounts, so the reintroduction phase is critical for determining the tolerated amount. The whole process can take months.

Risk of the low-FODMAP diet

While the low-FOMAP diet can be helpful for some people, it’s not a great option for others, and there are important risks to recognize. For starters, this diet is highly restrictive. While the initial restrictive phase is only temporary, nutritional deficiencies—especially inadequate fiber intake—can occur and may worsen GI symptoms. Additionally, the process of restricting foods can foster an environment for disordered eating making the diet unsuitable for anyone with a history of disordered eating or who may be at risk for developing disordered eating.

It should also be emphasized that the low-FODMAP diet is only one type of treatment option for people diagnosed with IBS and is often used with other therapies such as behavioral and medical interventions. The first step is to talk with your doctor to rule out other GI conditions that can have similar symptoms such as Crohn’s disease, small intestinal bacterial overgrowth (SIBO), and celiac disease. These conditions often require medical management and/or a different nutritional approach. Furthermore, this diet also may not work, even for those with IBS. According to Monash University’s research, GI symptoms have improved in 75% of people who were diagnosed with IBS and followed a low-FODMAP diet. As FODMAPs are not the root cause of IBS, restricting them isn’t going to work for all people with IBS.

Trying the diet

If you’re looking for GI symptom relief and are thinking about trying the low-FODMAP diet, speak with a registered dietitian nutritionist (RDN) first to discuss different treatment options. As IBS treatment is unique to each person, RDNs will assess, supervise, and collaborate with you to create a plan that best meets your needs. They’ll ensure that the diet is customized to your situation and will carefully plan each step to prevent common issues. An RDN will also ensure that the selected low FODMAP approach is evidence-based (given that there are several misguiding versions of the “low FODMAP diet” available on the Internet). While it’s no magical diet, research consistently shows that, with proper guidance, the low-FODMAP diet may help improve symptoms and quality of life for those with IBS.

Get to know the Author:

Lynne Lalor is from Colorado Springs, Colorado, and has lived in Colorado almost her whole life. Lalor graduated in May with a Bachelor of Science degree in Food Science and Human Nutrition. She was the KRNC Student Spotlight in April 2022, learn more about Lalor here.

More Information:

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