Monash FODMAP App Traffic Lights – How Are They Determined?

Researchers from Monash University’s FODMAP team conducted studies to identify the specific amount of FODMAPs that can induce symptoms in individuals with Irritable Bowel Syndrome (IBS).

Based on this research, they established ‘safe cut-off’ levels for FODMAPs in food. These cut-off levels represent the amount of FODMAPs that the majority of people with IBS can consume without experiencing IBS symptoms.

The Monash University FODMAP diet app uses a simple traffic-light system to categorise foods as:

• green (low in FODMAP, safe to eat),
• amber (moderate in FODMAP, intake should be limited), and
• red (high in FODMAP, intake should be avoided)

In this blog, we will explain how we get the overall FODMAP rating for a food (the large traffic light). Additionally, we will explain the small traffic lights and associated quantities.

Let’s start with the food testing.

The Monash FODMAP team collects food for analysis in our laboratory. Food testing of the individual FODMAPs (fructose, lactose, mannitol, sorbitol, GOS and fructans) takes a number of weeks to complete.

The overall FODMAP rating for a food (ie. the large traffic light) is based on the typical serving size of that particular food.

So what is a typical serving?

This amount is based on either;

• the recommended standard serving sizes given in the Australian Guide to Healthy Eating, such as:
  • 75 grams of vegetable
  • one medium-sized piece of fruit
  • 1 cup (250ml) of milk or plant-based milk
• the serving suggestions provided on the packaging of manufactured products, such as 2 slices of bread or 1 cup of pasta.

The Monash FODMAP team compares the laboratory results for a typical serving of a food with their ‘safe cut-off’ levels for FODMAPs and a large traffic light rating given. A food will be given an overall FODMAP rating green (low FODMAP), amber (moderate FODMAP) or red (high FODMAP).

What do the smaller traffic-light mean?

The small traffic light colour provides you with a guide to how each food's FODMAP rating changes at different serving sizes. The standard serve will always be the first traffic light, so foods may start green and go red as serves increase or start red and become green with smaller serves.

Laboratory testing can indicate that some foods are very low in FODMAPs and so a larger quantity may be consumed before quantities of FODMAPs become moderate (amber) or high (red).

Some foods, however, contain higher amounts of FODMAPs and so while there is a safe green serve, the rating quickly changes to amber and red. This means that you need to be careful about how much of these foods you consume in one sitting or meal.

When starting the Low FODMAP Diet Plan, it is advisable to primarily opt for foods with low FODMAP (green) ratings and recommended green serving sizes.

Good news coming through…

The Monash FODMAP team is currently working on including a red, amber and green traffic light rating for all foods found in the Food Guide. Stay tuned for the latest app updates which will be announced via our social media platforms.