What Foods Have Mannitol in Them?

November 18, 2025 •

3 min read

Mannitol is a type of sugar alcohol, or polyol, that occurs naturally in many fruits, vegetables, and fungi. Understanding what foods have mannitol in them is vital for managing digestive comfort, especially for people with irritable bowel syndrome (IBS) or those following a low-FODMAP diet.

Quick Summary

Explore which fruits, vegetables, and processed products contain mannitol, a high-FODMAP sugar alcohol. This guide details both natural sources and added forms, offering crucial insights for managing digestive health.

Key Points

Natural Sources: Mannitol is found naturally in foods like mushrooms, cauliflower, celery, watermelon, and clingstone peaches.
Processed Products: It is added to many 'sugar-free' items, including chewing gum, diet candies, and baked goods, and can be identified by the name or E-number E421.
Digestive Impact: Mannitol is a high-FODMAP polyol that can cause bloating, gas, and diarrhea in sensitive individuals, such as those with IBS.
FODMAP Diet: Managing mannitol intake is a key part of the low-FODMAP diet, especially during the elimination and reintroduction phases.
Substitutions: Lower-mannitol alternatives for common high-mannitol foods include carrots instead of celery, oyster mushrooms instead of button mushrooms, and berries instead of watermelon.
Label Reading: Check food labels for 'mannitol' or the additive number 'E421' to identify manufactured sources.

What is Mannitol?

Mannitol is a sugar alcohol (polyol) found naturally in plants and fungi and is about half as sweet as sugar. It is also manufactured as a low-calorie sweetener and used in 'sugar-free' products. Mannitol is poorly absorbed in the small intestine, and in sensitive individuals like those with IBS, it can cause digestive issues such as bloating and gas due to fermentation by gut bacteria. It is classified as a high-FODMAP carbohydrate, often restricted during a low-FODMAP diet.

Natural Sources of Mannitol

Mannitol is naturally present in many plant-based foods, with concentrations varying by type and serving size.

Vegetables

Some vegetables known to contain mannitol include cauliflower, celery, various mushrooms (like button, portobello, and shiitake, though oyster mushrooms are lower), butternut squash, snow peas, fennel, and leeks. Brown algae like seaweed and kelp are also significant sources.

Fruits

Fruits containing mannitol include watermelon and clingstone peaches, which have high levels, as well as olives and some types of figs in smaller amounts.

Processed Foods with Added Mannitol

Mannitol is used as a food additive (E421) for its sweetness and anti-caking properties.

Products containing added mannitol include:

Sugar-free items: Chewing gum, mints, diet candies.
Desserts: Baked goods, fillings, frozen desserts, and chocolate coatings.
Other products: Nutritional powders and some liquid medications.

Mannitol and the Low-FODMAP Diet

Due to poor absorption and subsequent fermentation in the large intestine, mannitol can trigger IBS symptoms. A low-FODMAP diet involves temporarily removing high-mannitol foods to assess symptom improvement, followed by a reintroduction phase to determine personal tolerance. Portion sizes are crucial, as small amounts may be tolerated while larger servings can cause issues.

Comparison of High vs. Low Mannitol Foods


Category	High Mannitol Foods	Low Mannitol Foods
Vegetables	Cauliflower, celery, mushrooms (button, portobello, shiitake), butternut squash, fennel, leeks	Broccoli, potatoes, carrots, spinach, zucchini, cabbage, bell peppers
Fruits	Watermelon, clingstone peaches	Berries (strawberries, blueberries), oranges, kiwi, pineapple, grapes
Dairy	None are sources	No change
Proteins	None are sources	No change
Sweets & Treats	Sugar-free gum, diet candies, certain baked goods	Regular candies (with sugar), products sweetened with stevia or monk fruit

How to Manage Mannitol Intake

To manage mannitol intake, learn which foods contain it naturally and in manufactured products. Read food labels for 'mannitol' or 'E421'. Substitute high-mannitol vegetables and fruits with lower-mannitol options like carrots instead of celery or berries instead of watermelon. Resources like the Monash University FODMAP Diet App can help with portion sizes and identifying tolerance. Be mindful of 'FODMAP stacking'.

Conclusion

Mannitol is a widespread sugar alcohol found in certain natural foods and added to many sugar-free products. Its poor absorption can cause digestive discomfort for sensitive individuals, especially those with IBS on a low-FODMAP diet. By identifying foods with mannitol and checking labels, intake can be managed. Substituting high-mannitol foods and controlling portion sizes allows individuals to minimize symptoms while maintaining a varied diet. Consulting a registered dietitian or using the official Monash FODMAP app is recommended for personalized guidance.

Visit the official Monash FODMAP website for more information on managing mannitol intake

Frequently Asked Questions

Mannitol is a sugar alcohol, or polyol, that occurs naturally in fruits, vegetables, and fungi. It is also manufactured for use as a low-calorie, sugar-free sweetener in many commercial products.

Mannitol is poorly absorbed by the small intestine and draws water into the gut through an osmotic effect. The unabsorbed portion then travels to the large intestine where it is fermented by gut bacteria, producing gas that can cause bloating, gas, and diarrhea, especially in people with IBS.

Common fruits that contain high levels of mannitol include watermelon and clingstone peaches. Some other fruits like olives also contain smaller amounts.

Vegetables known to be high in mannitol include cauliflower, celery, butternut squash, snow peas, fennel, and leeks.

Many sugar-free and diet products use mannitol as a sweetener. This includes chewing gum, mints, diet candies, chocolate coatings, some baked goods, and nutritional powders.

To identify mannitol on food labels, look for the word 'mannitol' or the food additive number E421 in the ingredient list.

Yes, many foods can be substituted. For example, swap high-mannitol cauliflower for broccoli or spinach, replace celery with carrots or bell peppers, and use oyster mushrooms instead of button mushrooms.