Are Grapes Low FODMAP: A Simple Guide for IBS Sufferers  

What is the FODMAP diet?

The low FODMAP diet is a temporary elimination diet for people with irritable bowel syndrome (IBS). Following the low FODMAP diet has been shown to help reduce IBS symptoms and allow people with IBS to find their unique tolerance to foods.

FODMAP stands for Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols. These are fermentable carbohydrates such as fructose, lactose, and others that can trigger IBS symptoms.

The low FODMAP diet starts with a strict elimination phase where only low FODMAP foods are eaten. Then there is a reintroduction phase where high FODMAP foods are systematically added back into the diet in order to test tolerance to each FODMAP category. This information is then used to create a maintenance diet where the goal is to eat the broadest possible diet with the least amount of IBS symptoms.

The low FODMAP diet can be very challenging to follow on your own, so it’s highly recommended to work with a specialized registered dietitian before starting the diet.

What are low FODMAP foods?

The process for classifying low and high FODMAP foods is very scientific. Foods are tested at various serving sizes to determine the amount of the different types of FODMAPs they contain. A low FODMAP food is below the set threshold for all the different FODMAPs at a particular serving size.

Examples of low FODMAP foods include:

• Protein sources: eggs, firm tofu, plain cooked meats, poultry, and seafood

• Fruits: kiwifruit, oranges, blueberry

• Vegetables: carrots, eggplant, green bell pepper

• Dairy & alternatives: almond milk, lactose-free milk and hard cheeses

• Nuts & seeds: walnuts, pumpkin seeds, peanuts

• Breads & cereals: rice, oats, wheat/rye/barley free breads

If you’re following a low FODMAP diet, it can be helpful to include a wide variety of low FODMAP foods in order to make up for what you’re eliminating.

Still, portion size impacts the FODMAP content of food. A small enough portion can change a high FODMAP food to a lower FODMAP food. Additionally, FODMAP tolerance varies between people. A low FODMAP food may still cause symptoms in some people.

Some healthcare professionals create their own low FODMAP diet handouts that contain lists of low and high FODMAP foods. Monash University, the leading authority on FODMAPs, has an app that you can use to search for individual foods. Food products that are certified low FODMAP will contain a seal on the label.

Are grapes low FODMAP?

Grapes contain a FODMAP called fructose, but there isn’t a clear consensus on the FODMAP content of grapes. This is because the two main apps, Monash University and FODMAP Friendly, have very different information. 

For example, FODMAP Friendly lists red seedless grapes as low FODMAP at a serving size of 150 grams (one cup). Whereas Monash lists red seedless grapes as low FODMAP at only 10 grams (that’s only two grapes!). Monash also says that both red and white seedless grapes are high FODMAP at servings of 75 grams (15 grapes) or above.

So why the differences? Apparently, Monash retested grapes in December 2021 and changed the low FODMAP serving size to six grapes. Then, in June 2024, Monash changed the low FODMAP serving size again to only two grapes.

It’s thought that changes in the environment, growing conditions, and storage conditions impact the FODMAP content of foods. Monash University is based in Australia, so we can’t say for sure if this applies to grapes all over the world. But many consider Monash University and their app to be the gold standard list and the primary source for the most up-to-date research on the low FODMAP diet.

It’s best to defer to your healthcare provider if you have questions about what foods you can and cannot eat during the elimination phase of the low FODMAP diet.

Low FODMAP Serving Sizes of Grapes

Grape TypeMonash AppFODMAP FriendlyRed Seedless Grapes10 grams (2 medium grapes)150 grams (1 cup)White Seedless Grapes11 grams (2 medium grapes)24 grams (6 small grapes)Red Globe GrapesNot available100 grams (24 small grapes)Black GrapesNot available100 grams (1 cup)

Red seedless grapes

• Low FODMAP serving size per Monash University app: 10 grams (2 medium grapes)

• Low FODMAP serving size per FODMAP Friendly app: 150 grams (1 cup)

White seedless grapes

• Low FODMAP serving size per Monash University app: 11 grams (2 grapes)

• Low FODMAP serving size per FODMAP Friendly app: 24 grams (6 small grapes)

*Note that Monash groups white / green grapes into a single category, whereas FODMAP Friendly just says “white.”

Red globe grapes

• Low FODMAP serving size per FODMAP Friendly app: 100 grams (1 cup)

• No data is available for red globe grapes on the Monash app

Black grapes

• Low FODMAP serving size per FODMAP Friendly app: 100 grams (24 small grapes)

• No data is available for black grapes on the Monash app

How do grapes affect people with IBS?

Given the differences between the two apps, it’s not fully clear how grapes may impact someone with IBS who is sensitive to excess fructose. However, symptoms of IBS can be unique to the individual. Some people may tolerate fructose and grapes better than other people. 

If you’ve already been eating grapes and tolerate them well, then there is likely no need to remove them. However, if you’re about to start a low FODMAP diet, it’s important to check with your healthcare provider about what resources you should follow during the elimination phase of the diet.

Other low FODMAP fruits to consider

Here is a list of low FODMAP fruits, according to the Monash app:

• Cantaloupe (¾ cup)

• Kiwi (2 medium)

• Mandarin (1 medium)

• Navel Orange (1 medium)

• Pineapple (peeled) (1 cup)

• Blueberries (1 cup)

Be sure to stick to a single serving size to avoid going over the low FODMAP threshold.

When to consult a healthcare professional

The low FODMAP diet is difficult to navigate alone. Trying to follow a low FODMAP diet for IBS on your own could potentially lead to undereating or nutrient deficiencies. The low FODMAP diet is meant to be temporary to help subside IBS symptoms and determine trigger foods. 

Research has shown that the diet is most successful when guidance is provided by a registered dietitian. Here at Season Health, we can match you with an experienced registered dietitian who can walk you through the low FODMAP diet step by step.