A Beginner's Guide to Low FODMAP

woman eating yogurt in kitchen

Digestive issues like bloating, gas, constipation, diarrhea, and stomach cramping can be extremely disruptive and uncomfortable. Many people struggle with these symptoms at some point in their life. These symptoms are often diagnosed as Irritable Bowel Syndrome (IBS) if they happen regularly.  

What is the Low FODMAP Diet?

One common recommendation for IBS symptom reduction is the low FODMAP diet. The low FODMAP diet or “FODMAP diet” works by eliminating foods that could make symptoms worse. FODMAP stands for fermentable, oligosaccharides, disaccharides, monosaccharides, and polyols. These terms refer to different kinds of sugars. In this case, “sugars” doesn’t mean sweets, but the naturally occurring sugars that are present in plant foods, dairy products, and certain grains. These sugars don’t get broken down effectively in the small bowel during digestion and as a result produce more gas. The excessive amount of gas can irritate the gut and cause symptoms like bloating, cramping, constipation and/or diarrhea in some people. These foods are “high FODMAP” whereas “low FODMAP” foods don’t produce as much gas and irritation. The FODMAP diet focuses on eating mainly from the low FODMAP food group and eliminating high FODMAP foods. 

As a newbie to the FODMAP diet, it can be confusing what foods to avoid. Many high FODMAP foods are healthy, such as apples, cauliflower, beans, honey, and yogurt. It can seem strange to eliminate these foods, but the low FODMAP diet has been shown to significantly reduce symptoms for many people(1). For recommendations on low FODMAP foods, check out this article.  

Not all high FODMAP foods will cause everyone to have symptoms. The goal of the diet is to eliminate all the high FODMAP trigger foods that could cause symptoms and slowly experiment over time with adding some back. This allows each individual following the diet to identify the specific foods that make their unique symptoms worse. 

Changing your Diet in the Short Term

This diet isn’t meant to be long-term. It is a short-term intervention followed by a slow re-introduction period. Following the low FODMAP diet for at least two weeks may help with digestive issues. For example, you follow the low FODMAP diet for a month then start eating apples again and notice more gas and diarrhea after eating the apples. By removing these foods for a short time, people on this protocol are able to find the specific foods that cause distress. 

Schedule an Appointment

The FODMAP diet can be intimidating and is complicated at first. Luckily there are a lot of resources that easily outline what foods are high vs. low FODMAP. If you are feeling lost about where to begin with the low FODMAP diet and want one-on-one support, specialists at Bastyr are here to help! The dietitians at the Bastyr clinic can provide helpful handouts for navigating the FODMAP diet, easy recipes and tricks that make it easier to follow. Schedule an appointment at Bastyr Center for Natural Health in Seattle and Bastyr University Clinic in San Diego today.  

Rosie Marsters is a Dietetic Intern at Bastyr and is passionate about the connection between nutrition, disease, and health. She believes that food can be used to create optimal health and support high performance. 



  1. Altobelli E, Del Negro V, Angeletti PM, Latella G. Low-FODMAP Diet Improves Irritable Bowel Syndrome Symptoms: A Meta-Analysis. Nutrients. 2017;9(9):940. Published 2017 Aug 26. doi:10.3390/nu9090940 

  1. Wei L, Singh R, Ro S, Ghoshal UC. Gut microbiota dysbiosis in functional gastrointestinal disorders: Underpinning the symptoms and pathophysiology. JGH Open. 2021;5(9):976-987. Published 2021 Mar 23. doi:10.1002/jgh3.12528 

  1. Monash University. FODMAPS and Irritable Bowel Syndrome. https://www.monashfodmap.com/about-fodmap-and-ibs/