E-numbers / Sweeteners / E953
also: isomaltitol · hydrogenated isomaltulose
A sugar alcohol made from sucrose, used to bulk out and sweeten sugar-free sweets and chocolates without the full calorie load of sugar.
Scan a barcode to check a food for isomalt. NutraSafe Pro · £6.99/month · iOS
Sweetener (Isomalt), Cream, Butter, Salt, Emulsifier (Soya Lecithin), Natural Peppermint Flavour (0.3%), Colour (Plain Caramel), Caramel, Natural Flavour, Sweetener (Sucralose)
At higher amounts, isomalt is not fully absorbed in the gut and ferments in the large intestine, causing bloating, stomach cramps and loose stools.
64
of the 43,325 UK supermarket foods we checked declare E953 in their ingredients
That is 0.1%, counted by its code or its name.
Counted by NutraSafe from UK supermarket ingredient lists, September 2026. How we counted
Why it’s worth knowing. At higher amounts, isomalt is not fully absorbed in the gut and ferments in the large intestine, causing bloating, stomach cramps and loose stools. Children reach this threshold at lower doses than adults.
Isomalt is a polyol (sugar alcohol) produced commercially from sucrose by a two-step enzymatic and hydrogenation process. It is a white crystalline powder with roughly half the sweetness of table sugar, very low solubility, and a near-zero glycaemic response because it is only partially digested in the small intestine.
It acts simultaneously as a bulk sweetener, humectant and texturising agent. Because it resists moisture uptake and does not caramelise easily, it holds the texture of confectionery products and hard-boiled sweets over time. Most of what is consumed passes undigested to the large intestine, where gut bacteria ferment it, generating short-chain fatty acids and gas.
Hard-boiled and sugar-free sweets, chocolate and chocolate-flavoured coatings, chewing gum, sugar-free cough drops and throat lozenges, ice cream, marzipan, baked goods labelled 'no added sugar', and some diabetic-targeted confectionery. On the label it appears as 'isomalt' or 'E953'.
Isomalt is only partially absorbed in the small intestine. The remainder reaches the colon, where bacteria ferment it, producing gas and drawing water into the bowel. At high doses this causes bloating, abdominal rumbling, cramps and loose or watery stools. Children reach the threshold where these effects occur at a lower intake than adults, as shown in controlled studies comparing isomalt sweets against sucrose sweets.
Children who ate 25g of isomalt-sweetened sweets had significantly more stomach-ache, abdominal rumbling and watery stools than those eating sucrose sweets; the same dose produced a mild laxative effect in children but not in the adult comparison group.
In a crossover study comparing sucrose, isomalt and lycasin, children showed greater gastrointestinal sensitivity to both polyols than adults, with isomalt producing more laxative episodes per unit dose in children.
Because laxation at high doses is well established, European and retained UK law requires that any food containing more than 10% added polyols, including isomalt, must carry the warning 'excessive consumption may produce laxative effects' on the label. This is a mandatory consumer alert, not a voluntary advisory.
Foods containing more than 10% added polyols must carry a mandatory laxation warning under assimilated EU Regulation 1333/2008 and related labelling provisions retained in UK law.
Because isomalt is poorly absorbed, it has a very low glycaemic index and does not meaningfully raise blood glucose. It is also non-cariogenic, meaning oral bacteria cannot ferment it to produce the acids that cause tooth decay. These properties are why it is widely used in diabetic confectionery and dental-friendly products.
Isomalt has a glycaemic index of approximately 2, compared with 65 for sucrose, and does not promote tooth decay because it is not metabolised by cariogenic oral bacteria.
People with irritable bowel syndrome or other functional gut conditions may find even moderate amounts trigger symptoms. Children are more sensitive than adults and reach the laxation threshold at lower doses. If you are buying sugar-free sweets or chocolates for a child, check the label for 'isomalt' or 'E953' and look for the mandatory laxation warning.
The gut-tolerance issue with isomalt is one of the better-documented effects of any food additive. It is real, dose-dependent, and more pronounced in children. The mandatory labelling requirement reflects this. Beyond laxation, the science on isomalt is thin: no carcinogenicity classification, no endocrine signal, no banned-substance status. The main practical concern is eating enough sugar-free sweets in one sitting, which is easier than most people assume, especially for children. The science on gut sensitivity in populations with IBS or gut conditions is not yet fully mapped.
No. Isomalt is approved for use in the UK under the retained EU food additives framework. It is a permitted sweetener and bulking agent in a wide range of food categories.
Isomalt and other polyols are only partially absorbed in the small intestine. What is not absorbed reaches the large intestine and is fermented by bacteria, producing gas and drawing water into the bowel. At doses typically around 20 to 30g in adults (less in children), this causes bloating, cramps and loose stools. UK law requires any product containing more than 10% added polyols to carry a warning about this on pack.
Mainly sugar-free and 'no added sugar' products: hard-boiled sweets, chocolates, chewing gum, cough drops, throat lozenges, some baked goods and diabetic-targeted confectionery. Check for 'isomalt' or 'E953' in the ingredients list.
Yes. Isomalt is produced from sucrose by an enzymatic and hydrogenation process and contains no animal-derived ingredients.
Last reviewed: 20 June 2026
It's the only app that does thisUKJaneK
You Need This AppGmac2005
Best AppGK getting skinny UK App Store reviews
NutraSafe reads the label and puts every additive into plain English, with the source, right in the app.
NutraSafe Pro · £6.99/month · iOS
