Maltitol
A sugar alcohol used as a lower-calorie sweetener in sugar-free and diabetic foods, with about 75% of the sweetness of sugar.
In large amounts maltitol causes bloating, wind and diarrhoea. EU and UK law requires a laxative-effect warning on products where polyols exceed 10% of the food. EFSA has also identified an outstanding genotoxicity data gap and called for new test data.
What is it?
Maltitol is a sugar alcohol (polyol) produced by hydrogenating maltose, which itself comes from starch. It occurs in very small amounts naturally in some plants. As a food additive it is produced commercially from corn, wheat or potato starch. It provides roughly 2.4 kcal per gram compared to 4 kcal per gram for sugar.
What does it do?
It provides sweetness without being fully absorbed in the small intestine. The unabsorbed portion passes to the large intestine where gut bacteria ferment it, which is why high doses produce a laxative effect. Because it raises blood glucose more slowly than sucrose, it is used in products marketed to people managing blood sugar, though it still has a meaningful glycaemic index (around 35) and is not carbohydrate-free.
Where you will see it
Sugar-free and reduced-sugar confectionery (chocolates, boiled sweets, chewing gum), diabetic-labelled biscuits and cakes, ice cream and frozen desserts, protein bars, jam and fruit preparations. On a UK label it appears as 'maltitol', 'maltitol syrup', or 'E965'.
What the science says
Laxative effect at higher intakes
Maltitol is poorly absorbed in the small intestine. The portion that reaches the large intestine is fermented by bacteria, producing gas and drawing water into the bowel. This causes bloating, flatulence and loose stools. The threshold varies between individuals but studies report noticeable effects in many adults at intakes above 20 to 30 grams in a single sitting. EU and UK food law mandates a laxative warning on any product where added polyols exceed 10% of the food's weight.
Doses of maltitol above roughly 20 to 30g in a single intake produced laxative symptoms including loose stools and flatulence in human volunteer studies.
EU Regulation 1333/2008 requires the label statement 'excessive consumption may have laxative effects' on foods where added polyols exceed 10% by weight.
Glycaemic response: lower than sugar but not negligible
Maltitol raises blood glucose and insulin to a lesser degree than sucrose, but the effect is not trivial. Its glycaemic index has been measured at approximately 35 in human studies, compared to around 65 for sucrose. For people with type 1 or type 2 diabetes who count carbohydrates, maltitol still contributes to glucose load and cannot be treated as a free food.
The glycaemic index of maltitol is approximately 35 and its insulinaemic index approximately 27, significantly lower than sucrose but not negligible in people managing blood glucose.
In a controlled study, maltitol chocolate raised blood glucose in type 1 diabetic subjects to a clinically meaningful degree, demonstrating that products labelled 'suitable for diabetics' containing maltitol still require insulin adjustment.
Genotoxicity data gap flagged by EFSA
As part of EFSA's systematic re-evaluation of all approved food sweeteners, EFSA issued a call for genotoxicity data specifically on maltitol (E965i), identifying the absence of a fully reliable in vitro micronucleus test as required by current guidance. This does not mean maltitol is known to damage DNA, but it means the standard battery of tests expected by regulators today is incomplete. EFSA has not yet published a completed re-evaluation opinion.
EFSA identified a missing in vitro micronucleus genotoxicity test for maltitol and issued a formal call for data, indicating the current evidence base does not meet current guidance requirements.
Dental health
Unlike fermentable sugars, maltitol is not readily broken down by mouth bacteria to produce the acids that cause tooth decay. Studies show it does not promote caries in the same way as sucrose. It is not, however, completely inert in the mouth.
Maltitol and maltitol syrup were found to be non-cariogenic or significantly less cariogenic than sucrose in both animal and human plaque pH studies.
Where it stands with the regulators
Who should be careful
People with irritable bowel syndrome (IBS) or other functional gut disorders may be more sensitive to the laxative and gas-producing effects at lower doses. Diabetics should not treat maltitol-sweetened products as carbohydrate-free; the glycaemic effect is lower than sugar but not zero. Look for 'maltitol', 'maltitol syrup' or 'E965' on the ingredients list.
The honest read
Maltitol is one of the most widely used polyol sweeteners and has been in the food supply for decades. The laxative effect is real, dose-dependent and individually variable: it is not a theoretical concern. The glycaemic point matters practically for diabetics misled by 'suitable for diabetics' labelling on products that still raise blood sugar. The outstanding genotoxicity data call from EFSA is a regulatory housekeeping gap, not a known hazard, but it means the modern standard evidence dossier is incomplete. The re-evaluation outcome will determine whether any regulatory action follows.
Related additives
Common questions
Is E965 banned in the UK?
No. Maltitol (E965i) and maltitol syrup (E965ii) are both approved food additives in the UK under the retained UK food additives regulations derived from EU Regulation 1333/2008. They appear on the UK FSA approved additives list.
Does maltitol cause stomach problems?
It can. Maltitol is a polyol that is poorly absorbed and fermented in the large intestine. At intakes above roughly 20 to 30g in a single sitting many people experience bloating, wind or loose stools. Individual tolerance varies. UK law requires a laxative warning on products where added polyols exceed 10% of the food's weight.
What foods contain E965?
Mainly sugar-free and reduced-sugar products: chocolates, boiled sweets, chewing gum, biscuits and cakes, protein bars, ice cream and diabetic-labelled confectionery. Check the ingredients list for 'maltitol', 'maltitol syrup' or 'E965'.
Is E965 vegan?
Maltitol itself is derived from plant starch (corn, wheat or potato) and is vegan. Whether a product containing it is vegan depends on the other ingredients.
Sources
- UK FSA Approved Additives and E Numbers
- EFSA Call for Data: Genotoxicity data on maltitol (E 965 i)
- Livesey G, Health Potentials of Polyols as Sugar Replacers, Nutrition Research Reviews (2003)
- Maltitol: Analytical Determination Methods, Applications in the Food Industry, Metabolism and Health Impacts (PMC, 2020)
- EU Regulation 1333/2008 on food additives (EUR-Lex)
- Livesey G, Nutrition Research Reviews 2003 (polyol glycaemic index)
See this on every food you scan
NutraSafe reads the label and puts every additive into plain English, with the source, right in the app.
Get NutraSafe on the App Store