Overview
About Mannitol
Mannitol is graded high FODMAP and high polyol in our data, and it is the polyol most people eat without ever hearing its name.
Monash keeps sorbitol and mannitol apart because the food lists barely overlap: sorbitol belongs to stone fruit, apples and pears, while mannitol is the one in mushrooms, cauliflower, celery and snow peas, plus the E421 dusted onto sugar-free gum and pressed into tablets. Our data collapses both into a single polyols column, so a high polyols grade on this page means mannitol specifically. On everything else it is clean: no histamine, no salicylate, no oxalate, no gluten, no lactose, no free glutamate. The malabsorption is the entire story.
Sensitivities
How Mannitol scores
Watch for
What trips people up
- Graded high on FODMAPs and polyols. Only part of a mannitol dose is absorbed in the small intestine, so the remainder drags water into the bowel and then ferments in the colon: bloating, cramping and loose stools within hours.
- This is the polyol behind mushrooms, cauliflower, celery and snow peas. People who fail a cauliflower or mushroom challenge on a low FODMAP reintroduction are usually reacting to mannitol, not to fructans.
- US labels must carry the statement "Excess consumption may have a laxative effect" when foreseeable daily intake reaches 20 grams of mannitol (21 CFR 180.25). Treat that as a regulatory floor, not a personal threshold: sensitive guts react well below it.
- Graded poorly for SIBO fermentation. Anything that reaches the colon undigested feeds an overgrown small intestine on the way, and mannitol is fermentable by definition.
- Scan for E421 rather than the word mannitol. It also appears as an anticaking agent and as a filler in medicines and supplements, which is an easy hidden dose to miss when you are logging food only.
Diet fit
Where it fits
Swap ideas
More alternatives
FAQ
Common questions about Mannitol
Is mannitol high FODMAP?
Yes. Mannitol is graded high on both the overall FODMAP score and the polyols column. It is incompletely absorbed in the small intestine, so it acts osmotically and then ferments in the colon. Monash lists it as one of the two polyols to eliminate in the elimination phase.
What is the difference between mannitol and sorbitol?
They are chemical isomers with the same formula and very similar gut behaviour, but they occur in different foods, which is why Monash tests and reports them separately. Sorbitol dominates stone fruit, apples, pears and sugar-free gum. Mannitol dominates mushrooms, cauliflower, celery, snow peas and watermelon. Our data reports one shared polyols column, so if you tolerate apples but not mushrooms, mannitol rather than sorbitol is the likely culprit.
Which foods are naturally high in mannitol?
Mushrooms are the classic one, along with cauliflower, celery, snow peas, watermelon, sweet potato and some seaweeds. Added mannitol shows up as E421 in sugar-free chewing gum, mints, lozenges and as a coating or bulking agent in tablets.
Why is mannitol also used as a medicine?
The same property that upsets the gut is useful clinically. Given intravenously, mannitol pulls fluid across membranes and is used to lower raised intracranial pressure and eye pressure. Inhaled as a dry powder, it is used as a bronchial provocation test for airway hyperresponsiveness and to help clear mucus in cystic fibrosis. None of this means the food additive is a drug, but it does explain why the substance moves water so effectively.
References
Read the background
Ratings reflect the Triggerbites ingredient database and may vary with portion size and preparation.