Sabine Hossenfelder has talked about sugar alcohols causing her gut trouble. The key point is medically plausible: sorbitol and xylitol can cause GI symptoms, especially in sensitive people or at higher doses.
Why they cause gut problems Sorbitol and xylitol are sugar alcohols / polyols. They’re only partly absorbed in the small intestine. The unabsorbed part can:
- Pull water into the bowel → loose stool or diarrhea
- Get fermented by gut bacteria → gas, bloating, cramps
- Act like a laxative, especially with repeated or large intake
Common symptoms:
- bloating
- gas
- abdominal cramps
- urgency
- diarrhea / loose stools
- sometimes nausea
Sorbitol vs xylitol
- Sorbitol is especially notorious. It’s found in sugar-free gum/candy and naturally in prunes, pears, apples, apricots, etc. It’s one reason prunes can work as a laxative.
- Xylitol can also cause bloating, gas, upset stomach, and diarrhea, though tolerance varies.
Who is more likely to react?
People with:
- IBS
- FODMAP sensitivity
- SIBO or gut dysbiosis
- recent antibiotic use
- generally sensitive digestion
Some people react to small amounts; others tolerate moderate amounts fine.
Practical test If you suspect this:
- Avoid sorbitol, xylitol, maltitol, mannitol, isomalt for 1–2 weeks.
- Check labels on “sugar-free,” “keto,” gum, mints, protein bars, cough drops.
- Reintroduce one at a time in small amounts.
- If symptoms return, you’ve likely found a trigger.
Safety note – common sense, not medical advice
These symptoms are usually not dangerous and improve after stopping the sweetener. But see a clinician if you have blood in stool, weight loss, fever, severe pain, dehydration, or persistent diarrhea.
Sources: Harvard Health, NHS, Yale New Haven Hospital, UC Davis Health, and systematic reviews on polyols/GI symptoms.