Let’s Talk about Mannitol & the Low FODMAP Diet

Mannitol & The Low FODMAP Diet

'Raw Sweet Potato' by mama_mia licensed under Shutterstock Standard Image.

What is Mannitol?

Love sweet potato? But can’t tolerate large serves? Then you might have issues absorbing mannitol. Mannitol is a high FODMAP sugar alcohol and it belongs in the ‘Polyol’ group within the FODMAP acronym. This sneaky FODMAP occurs naturally in a range of fruits and vegetables, and it can also be manufactured and added to our food. Check out my article to find out where mannitol likes to hide.

Where is Mannitol Found?

Mannitol naturally occurs in high levels in a range of fruit and vegetables like watermelon, clingstone peaches, button mushrooms, cauliflower, celery, snow peas, butternut squash and sweet potato (Monash University App, 2016; Muir et al., 2009). It’s important to remember that many high FODMAP foods like butternut squash, sweet potato and snow peas, have smaller serves that are low FODMAP (explore the Monash Low FODMAP app for more information).

Mannitol can also be manufactured from fructose sourced from cornstarch (The Sugar Association, 2015). Manufactured mannitol is used as a sweetener and is added to a wide range of products from ‘sugar free’ foods and beverages, through to protein powders, baked goods, and chewing gum. It is also added to some liquid medications like cough syrups, cold medicine, and liquid pain relief.

Can Mannitol be Called Anything Else?

Check processed products for mannitol food additive number e421 or 421 (Food Standards Agency, 2014). In the USA mannitol should be called by its full name in the ingredient list.

Why is Mannitol an Issue?

Mannitol is a polyol and only one-third of the polyols consumed are actually absorbed by our bodies. The level of absorption depends on the type of polyol and the individual. When polyols are poorly absorbed, our gut bacteria feast on the sugars and rapidly ferment them, causing IBS symptoms (Mansueto et al., 2015; Monash University App, 2016). Polyols are also natural laxatives, as they draw water into the large intestine when they are poorly absorbed, which stimulates bowel movements (Mansueto et al., 2015; Monash University App, 2016).

Do Mannitol Levels Vary Between Foods?

According to a research paper published by a Monash University research team in the Journal of Agricultural and Food Chemistry, the mannitol levels between different fruits and vegetables do vary. Below is a table with a few examples.

High FODMAP Fruit

Grams of Mannitol per 100g of fresh weight of sample

Low FODMAP Serving Size

Clingstone peach









Butternut squash*



Button mushrooms









Fennel bulb*



Mange tout*


17g (5 pods)

Snow peas*


17g (5 pods)

Sweet potato*



 *These vegetables have small serves that are low FODMAP. N/A stands for ‘Not Available’.

(Information in table sourced from: Monash University App, 2016; Muir et al., 2009)

Can You Cook With Foods High In Mannitol?

During the elimination phase of the low FODMAP diet, make sure you avoid cooking with foods that are high in mannitol, unless they have a low FODMAP serving size (check the Monash Low FODMAP app for serving size guidelines). For example, in the elimination phase of the low FODMAP diet then you can enjoy a low FODMAP 70g serve of sweet potato. However, you want to make sure you do not use any other safe serves of high or moderate FODMAP foods in the same meal. For example, combining butternut pumpkin and sweet potato in one meal, as this might take you over the FODMAP threshold level. Otherwise it is recommended that you avoid cooking with foods that are high in mannitol (button mushrooms, cauliflower, clingstone peach, watermelon), instead focus on low FODMAP ingredients.

Also keep in mind that mannitol is water soluble (Drug Bank, 2013), just like the fructans in onion and garlic. This means that the mannitol will leach out of the food and into the liquid in the meal. For example, if you cook a soup using button mushrooms, the mannitol will leach out of the mushroom and into your soup, raising the overall FODMAP content. Even if you pick the mushrooms out of the meal you could still consume a high FODMAP load.

Final Thoughts

Mannitol is a sugar alcohol that can sneak into our diet through certain fruits, vegetables and processed products. Make sure you check food labels for mannitol food additive name e421. During the elimination phase of the low FODMAP diet, make sure you avoid foods that are high in mannitol, unless they have a safe serving size.


  1. Monash University App. Food Guide. The Monash University Low FODMAP Diet App. 2016: Version 1.6.1(305). Date retrieved: 2016-05-23. Retrieved from :http://www.med.monash.edu/cecs/gastro/fodmap/iphone-app.html. Accessed: 2016-05-23. (Archived by WebCite® at http://www.webcitation.org/6Wog73c8B)
  2. Muir, J., Rose, R., Rosella, O., Liels, K., Barrett, J., Shepherd, S., & Gibson, P. Measurement of Short-Chain Carbohydrates in Common Australian Vegetables and Fruits by High-Performance Liquid Chromatography (HPLC). Journal of Agricultural And Food Chemistry. 2009: Volume 57: Issue 2: p. 554-565. Retrieved from:http://pubs.acs.org/doi/abs/10.1021/jf802700e. Retrieved on: 2016-05-30.
  3. The Sugar Association. Sugar Alcohols. The Sugar Association. 2015. Retrieved from:http://www.sugar.org/other-sweeteners/sugar-alcohols/. Retrieved on: 2015-05-17.(Archived by WebCite® at http://www.webcitation.org/6YbYCAip1)
  4. Food Standards Agency. Current EU approved additives and their E Numbers. Food Standards Agency. 2014-12-30. Retrieved from:https://www.food.gov.uk/science/additives/enumberlist. Retrieved on: 2015-10-18.(Archived by WebCite® at http://www.webcitation.org/6cNpXGFub)
  5. Mansueto, P., Seidita, A., D’Alcamo, A., Carroccio, A. Role of FODMAPs in Patients with Irritable Bowel Syndrome: A Review. Nutrition in Clincial Practice Journal. 2015-02-18. DOI: 10.1177/0884533615569886. Retrieved from http://ncp.sagepub.com/content/early/2015/02/17/0884533615569886
  6. Drug Bank. Mannitol. Journal of Agricultural And Food Chemistry. 2016-05-29. Retrieved from:http://www.drugbank.ca/drugs/DB00742. Retrieved on: 2016-05-29.

Post your comment


  • Lou 28/11/2016 11:31pm (12 months ago)

    Thank you so much for explaining this so clearly. I have a strong reaction to mushrooms and wanted to unterstand why. it's also nice to know there may be other mushrooms i CAN eat, though I'm not really game to trial and erroe!

    • Alana Scott 29/11/2016 2:22am (12 months ago)

      Hi Lou,

      So glad you found the article useful! Right now it looks like portobello mushrooms, shiitake mushrooms and button mushrooms all contain mannitol so avoid those. In the meantime if you do want to try a mushroom, then Shimeji Mushrooms have been tested by FODMAP Friendly and they appear low in mannitol. I hope that helps!

  • Gillian ROWLES 04/01/2017 5:19pm (11 months ago)

    Why do pharmaceutical companies put it in tablets. Seems silly.

    • Alana Scott 05/01/2017 1:41am (11 months ago)

      It can be really frustrating. Just remember when it comes to tablets the amount of mannitol in the tablet is probably within low FODMAP levels. Mannitol in medication normally only becomes a problem when it is included in liquid suspensions (like cough mixture) or in throat lozenges.

  • Suzanne 29/07/2017 12:56pm (4 months ago)

    Thank you for the great information! The FODMAP diet helped me determine that mannitol was my biggest issue. I love Cauliflower but it was making me miserable. Symptoms would happen a day to two later. So I never made the connection. Been avoiding it and a few other foods for the last year and it's been wonderful!!

    • Alana Scott 30/07/2017 1:09am (4 months ago)

      Hi Suzanne,
      It's great to hear that you have gained good symptom control by avoiding a few high FODMAP foods. Well done! Also it is really common for FODMAP related symptoms to start occurring about 24 hours later as the FODMAPs have to make it all the way to our intestines before the reactions start to take place.

  • Aggie 13/09/2017 7:47am (2 months ago)

    Hi Alana,
    Thank you for all your posts! Your website is so practical and easy to navigate, and unbelievably helpful.
    I react to Mannitol but not Sorbitol, so find the Monash FODMAP App rather a blunt tool as it lumps them together as Polyols without differentiating. Any idea whether they might add another column in the future?

    • Alana Scott 13/09/2017 10:49pm (2 months ago)

      Hi Aggie,
      Thank you so much for the lovely feedback - it's great to know that you find my website useful.

      I suggest you create a quick list of mannitol containing foods on your phone to have as a quick reference guide.

      In regards to the Monash app I agree that it would be a lot more helpful if they split the polyol filter. I don't know if they plan to do this in the future but I do know you can provide them with feedback through the app (under settings) so it might be a good idea for you to put in a request.

      I hope that helps.

RSS feed for comments on this page | RSS feed for all comments