Maltitol
1. Identity and Chemical Characterization
Maltitol is a sugar alcohol (a polyol) used as a sugar substitute and laxative.
In chemical terms, it is known as 4-O-α-glucopyranosyl-D-sorbitol, and it is a disaccharide produced by hydrogenation of maltose obtained from starch.
This compound is formed from a glucose unit connected through the glucosidic OH with a glucitol (sorbitol) unit.
It has the molecular formula C₁₂H₂₄O₁₁ and appears as a white crystalline powder with a melting point of 148–151°C, exhibiting high solubility in water and good thermal and chemical stability.
The European food additive number E965 refers to both maltitol crystalline and syrup.
Maltitol is one of seven polyols legally allowed as nutritive or bulk sweeteners in the European Union: sorbitol (E420), mannitol (E421), isomalt (E953), maltitol (E965), lactitol (E966), xylitol (E967), and erythritol (E968).
1.1 Physical and Sweetness Properties
Maltitol has 75–90% of the sweetness of sucrose (table sugar) and nearly identical properties, except for browning.
In its crystallized form it measures the same bulk as table sugar but does not caramelize nor participate in Maillard reactions upon heating due to its relative chemical inertness.
Maltitol is a white crystalline powder that acts as a bulking agent, an emulsifier, a humectant, a stabilizer, a sweetener, and a thickener.
It exhibits a negligible cooling effect in the mouth compared to most other polyols.
1.2 Common Forms and Commercial Preparations
Due to its sucrose-like structure, maltitol is easy to produce and is made commercially available in crystallized, powdered, and syrup forms.
It is available in both crystalline powder (E965i) and syrup or solution (E965ii); E965i can be used to replace sugar while E965ii can substitute glucose syrup.
The reaction product of hydrogenation is maltitol syrup of different grades — with 50–55%, 72–77%, and 80–90% of maltitol — which can be subjected to a crystallization process, thus leading to maltitol powder.
Maltitol is used in commercial products under trade names such as Lesys, Maltisweet, and SweetPearl.
Commercially, maltitol is also one of the largest produced polyols with an approximate volume of 160,000 MT, including hydrogenated starch hydrolysates.
2. Natural Sources and Production
2.1 Natural Occurrence
Maltitol is a sugar alcohol, or polyol, a member of a group of carbohydrates that occur naturally in various fruits and vegetables.
Small amounts of maltitol occur naturally in chicory leaves and in roasted malt; commercially, maltitol is produced from the starch of cereals such as corn, potatoes, and wheat.
Although maltitol occurs in trace amounts in nature, extraction from those sources is not a viable production method.
2.2 Industrial Manufacturing
Maltitol is produced by chemical hydrogenation of maltose, which can be obtained by enzymatic degradation of starch under conditions similar to those used for other starch hydrolysates. The starting material can be the different commercially available starches, including corn, potato, and others.
A partially degraded starch, which can be obtained by treatment with diluted hydrochloric or sulphuric acid and subsequent neutralization or with heat-stable α-amylase, is then subjected to enzyme treatment for further degradation to maltose-rich products.
The industrial process of maltitol production is mainly based on catalytic hydrogenation (100–150°C; 100–150 bar) of glucose syrup with high maltose levels, obtained by enzymatic hydrolysis of starch.
On a commercial scale, maltitol is produced by hydrogenation of corn syrup with high maltose content prepared by enzymatic hydrolysis of starch. After purification and concentration of the hydrogenated syrup, a crystalline product with a maltitol content of between 90% and 99%, plus small amounts of sorbitol and hydrogenated trisaccharides, is obtained.
Maltitol syrup — a hydrogenated starch hydrolysate — is produced by hydrogenating corn syrup; this product contains between 50% and 80% maltitol by weight. The remainder is mostly sorbitol, with a small quantity of other sugar-related substances.
3. Traditional and Historical Use
Maltitol as a distinct compound has no traditional medicinal history in the sense associated with plant-derived botanical ingredients, because it does not occur in nature in physiologically significant quantities and was not identified or isolated until the modern industrial era.
Although maltitol itself is a relatively modern discovery, sugar alcohols have historical roots in medicinal and health remedies; traditional healers often used naturally occurring sugar alcohols found in fruits and vegetables to prepare soothing syrups and tonics, valuing their gentle sweetness and digestive benefits.
The precursor compound maltose has an ancient history: it is produced during the malting and fermentation of grain, a process dating back thousands of years in beer and bread-making cultures across East Asia, the Middle East, and Europe.
Maltitol is a sugar substitute classified as a polyol; this sweetening agent has been used in the food industry for years and is considered a natural, low-calorie alternative to sugar. It is commonly added to chewing gums, sugar-free cookies, and reduced-fat food products.
Its widespread adoption as a food ingredient began in the latter decades of the twentieth century, expanding alongside the global market for reduced-calorie and diabetic-suitable foods.
4. Key Constituents, Chemistry, and Mechanisms of Action
4.1 Chemical Structure
Sugar alcohols have a general chemical formula H(HCHO)n+1H. These compounds are hydrogenated forms of corresponding carbohydrates, produced by reduction of their carbonyl groups to primary or secondary hydroxyl groups. The corresponding sugars are usually aldoses, and the resulting polyols are therefore called alditols.
Manufacturers use the catalytic hydrogenation of D-maltose to make a hydrogenated disaccharide consisting of a glucose molecule and a sorbitol molecule bound together.
Maltitol's pyrolyzate composition is basically an average of the composition of the pyrolyzates of its two molecular moieties (glucose and glucitol), such that little interaction appears to occur between these two parts during pyrolysis. This effect is very likely caused by the relatively weak ether bond between the sugar and the alcohol.
4.2 Metabolic Pathway and Absorption Mechanism
There is no active transport mechanism for maltitol; before absorption, the molecule must be enzymatically hydrolyzed to glucose and sorbitol, as maltitol molecules are too large to be absorbed by simple diffusion. Because this process is quite slow, the absorption rate varies between 5% and 80%. Intact molecules of maltitol that are not absorbed are moved to the lower gut, where they undergo fermentation, which can result in osmotic laxation.
One detailed study concluded that maltitol is partially hydrolyzed in the stomach, partially absorbed intact from the small intestine, and partially degraded by gut flora into volatile fatty acids, which are easily absorbed and utilized by the microbiota.
Maltitol provides between 2 and 3 kilocalories per gram (8–10 kJ/g). It is largely unaffected by human digestive enzymes and is fermented by gut flora, with about 15% of the ingested maltitol excreted unchanged in the feces.
The remaining 50–60% of unabsorbed maltitol reaches the colon, where it undergoes fermentation by gut microbiota, producing short-chain fatty acids (SCFAs), hydrogen, and methane gases.
Given its slow absorption, the insulin response associated with its ingestion is significantly reduced.
4.3 Caloric Value Compared to Sucrose
Maltitol's sweetness is pleasant and clean and accounts for up to 90% of that attributed to sucrose, but its caloric value is 2.1–2.4 kcal/g.
As a result, maltitol has just 2.1 calories per gram (kcal/g), nearly half of the caloric value of sucrose (4.0 kcal/g), and is therefore useful in the production of sugar-free products, especially sucrose-free chocolate, confectionery, and ice cream.
Because maltitol is slowly absorbed by the body, part of the ingested substance reaches the large intestine where metabolism yields fewer calories.
4.4 Oral Bacterial Metabolism
Maltitol is not metabolized by oral bacteria, so it does not promote tooth decay.
Polyols such as maltitol, sorbitol, and xylitol do not undergo fermentation by microorganisms and plaque of the oral cavity, and maltitol is non-cariogenic in nature by inhibiting glucan synthesis.
Major mechanisms involved in these oral health benefits appear to include lack of acidogenic potential, stimulation of the salivary flow, antimicrobial effect, and limitation of dental plaque formation.
5. Scientific Evidence by Area of Use
5.1 Blood Glucose and Insulin Response (Glycemic Effects)
Evidence summary: Multiple human clinical trials of moderate quality demonstrate that maltitol elicits a substantially lower glycemic and insulinemic response than glucose, though its glycemic index (GI) is notably higher than that of most other polyols, making it less suitable than alternatives such as erythritol for individuals with diabetes.
One study objective was to determine glycemic response (GR) to a high-GI (glucose) and low-GI (maltitol) test drink in subjects of different ethnic origin. In a randomized, single-blind crossover trial, 10 white, 10 South Indian, and 10 Chinese subjects consumed either glucose or maltitol test drink containing 50 g of one of the test products on different occasions. Capillary blood glucose samples were taken at multiple timepoints before and after consumption. The incremental area under the curve for glucose and maltitol were not significantly different between the three ethnic groups, indicating that maltitol's reduced glycemic impact is consistent across ethnicities.
In a study following FAO recommendations, mean blood glucose levels were significantly lower after the consumption of maltitol compared with glucose from timepoints 15 to 90 min. The glycemic response (GR) of maltitol was found to be 20.4 ± 9.3% of the glucose GR. After maltitol consumption, mean insulin blood levels were also significantly lower from timepoints 15 to 120 min compared with the reference subjects; the insulinemic response (IR) of maltitol was found to be 17.8 ± 9.9% of the glucose IR.
This study was conducted in 12 subjects given 50 g dissolved in 150 ml of mineral water after an overnight fast.
Maltitol has a reported glycemic index (GI) of 35, which is significantly higher than other polyols like erythritol or mannitol (GI of 0).
This results in a notably higher impact on blood sugar, potentially causing spikes in individuals with diabetes or insulin resistance. Maltitol also has a reported insulin index (II) of 27.
In a preclinical investigation, maltitol inhibited glucose absorption in isolated rat jejunum and increased glucose uptake in isolated rat psoas muscle in the presence of insulin, but not in its absence. However, maltitol did not significantly alter small intestinal glucose absorption or blood glucose levels, nor gastric emptying and digesta transit, in normal or type-2 diabetic rats in vivo. The results suggest that maltitol may not be a suitable dietary supplement as an anti-diabetic food ingredient to improve glycemic control. This preclinical finding, which conflicts with some human data, illustrates that in-vivo translation of in-vitro effects is not straightforward.
Limitations: Most human glycemic response trials involve small sample sizes (12–30 subjects), short follow-up periods, and use the compound in isolation (dissolved in water) rather than in realistic food matrices. The relationship between acute glycemic measurements and long-term metabolic outcomes in people with diabetes has not been established by clinical trials specifically for maltitol.
5.2 Dental Caries and Oral Health
Evidence summary: Multiple randomized clinical trials in children and adults provide moderate-quality evidence that maltitol, particularly when delivered in chewing gum, reduces plaque acidogenicity, cariogenic bacterial counts, and plaque formation compared to control conditions, though effects are generally comparable to — not superior to — those of xylitol.
In a controlled trial, maltitol and xylitol chewing gums led similarly to a higher plaque pH (measured as area under the curve, p ≤ 0.05) on both short-term (at baseline after first chewing gum consumption) and long-term (after 4 weeks of daily consumption) evaluations, with or without saliva stimulation compared with both control and placebo groups. They led to a decrease in plaque growth (p = 0.02) over the experimental period compared to controls, and significantly reduced the concentration of four cariogenic bacteria species (p ≤ 0.05) in dental plaque compared to gum base. Sugar-free chewing gum sweetened with either maltitol or xylitol can similarly reduce plaque acidogenicity compared to gum base through a decrease in oral bacteria presence.
In an open-label clinical study, sucrose was completely replaced with maltitol (minimum 45%) and steviol glycoside (0.05%) in chocolate. Salivary pH was measured at baseline and at 0, 1, 2, and 4 hours after test product consumption, and saliva samples were collected for measurement of Streptococcus mutans colonies at baseline, 0 h, and 4 h after consumption. A statistically significant increase in salivary pH from baseline at 0 h (p = 0.0181) and a reduction in S. mutans formation from baseline to 0 h and 4 h (p = 0.0001) were noted. The conclusion was that maltitol-based sugar-free chocolates were devoid of cariogenic potential.
One study aimed to determine the composition of dental plaque microbiota in patients with active caries before and after using a chewing gum supplemented with maltitol. Forty subjects with active caries were randomly allocated to chew maltitol gum or gum base for two weeks, and a healthy control group used gum base for two weeks. Plaque samples were collected before and after treatment, and the microbiota was analysed by pyrosequencing of 16S rRNA genes. There was no difference in the structure of bacterial communities between groups, but there was a significant difference in community membership between groups (p = 0.009).
In a randomized clinical trial among schoolchildren, xylitol or sorbitol/maltitol reduced the amount of acid production in saliva and dental plaque, but only xylitol interfered with microbial composition.
In another randomized clinical trial, Lenkkeri et al. studied caries-preventive effects of xylitol/maltitol and erythritol/maltitol lozenges in children; these interventions did not provide additional preventive benefits when compared with comprehensive prevention.
Limitations: Many studies are industry-sponsored, involve short follow-up periods (4 weeks), and use maltitol as one component of a multi-ingredient gum. The reduction in plaque biomarkers does not yet translate into long-term demonstrated reductions in clinical caries incidence in dedicated maltitol-specific controlled trials.
5.3 Gastrointestinal Tolerance and Microbiota Effects
Evidence summary: Human studies confirm a dose-dependent laxative effect for maltitol at higher intakes. Evidence for prebiotic effects (stimulation of bifidobacteria) is preliminary and comes from small studies with mixed designs.
A double-blind randomized cross-over study evaluated gastro-intestinal tolerance to maltitol. Twelve healthy volunteers ingested maltitol or sucrose throughout the day, either occasionally (once a week) or regularly (every day for two 9-day periods), with daily doses increased until diarrhea or a severe digestive symptom occurred, defining the threshold dose (TD). In the occasional-consumption period, the mean TD was 92 ± 6 g with maltitol and 106 ± 4 g with sucrose (p = 0.059). The mean intensity of digestive symptoms was 1.1 versus 1.3, respectively (not significant). However, diarrhea appeared in six subjects receiving maltitol versus one receiving sucrose (p = 0.035).
Another study demonstrated that osmotic diarrhea appeared at doses of maltitol of approximately 90 g and transitory osmotic diarrhea was caused at a dose of 45 g.
A dose-dependent relationship for gastrointestinal symptoms has also been seen with isomalt, lactitol, and maltitol, consistent with the pattern observed with other polyols.
To evaluate short-term digestive tolerance and glycaemic response, 36 healthy subjects aged 18–60 years were recruited; 32 completed the study. Subjects consumed six different mixtures of dextrose, maltitol, and short-chain fructo-oligosaccharides (scFOS) added in a chocolate dairy dessert at a dosage of 35 g. The subjects reported the intensity of four gastrointestinal symptoms, number of bowel movements, and stool frequency for 48 h after consumption. A subgroup of 18 subjects also provided blood samples 2 h after intake to evaluate postprandial glycaemic and insulinaemic responses. The composite score calculated from flatulence, borborygmi, bloating, and discomfort was significantly higher for all desserts containing maltitol.
An optimal dose of 34.2 g for maltitol plus polydextrose significantly increased the numbers of faecal bifidobacteria, lactobacilli, and short-chain fatty acids after maltitol ingestion compared to sucrose intake.
Several polyols, including isomalt and maltitol, increase bifidobacteria numbers in healthy subjects, and these polyols can have prebiotic actions.
To date, however, not enough data are available to determine the specific effects of maltitol on gut microbiota, and more studies are considered necessary.
Limitations: The prebiotic finding was based on a food containing multiple functional ingredients (maltitol combined with polydextrose), making it impossible to attribute effects exclusively to maltitol. No large, controlled, long-term trials have been conducted on maltitol's independent effects on the gut microbiome in humans.
5.4 Calorie Reduction and Body Weight Management
Evidence summary: Maltitol's lower caloric value (approximately 2.1–2.4 kcal/g versus sucrose's 4 kcal/g) theoretically supports calorie reduction, but there are no clinical trials examining maltitol specifically as an intervention for body weight loss or management. Its contribution to reduced-calorie food formulations is well-established at the formulation level.
A survey of products shows that maltitol is used in food mostly in sweet food categories such as cakes, pastries, sugar confectionery, chocolate, chewing gum, and snack bars, as well as a tabletop sweetener, because it has a similar sweetness to sucrose.
Although maltitol is often used to replace sugars in the manufacture of sugar-free foods, it may also be used to replace fat as it gives a creamy texture to food.
When consumed excessively, maltitol still contributes to energy intake and, therefore, weight gain. Although it has a lower caloric value than sugar, maltitol still provides energy.
5.5 Use in Diabetic-Suitable Formulations
Maltitol is used to replace table sugar because it is half as calorific, does not promote tooth decay, and has a somewhat lesser effect on blood glucose.
When applied simultaneously with short-chain fructo-oligosaccharides in sugar-free food product formulations, it lowers postprandial glycaemic responses.
However, its glycemic index of 35 — high compared to most polyols — means it is considered less appropriate than lower-GI alternatives for individuals requiring strict glycemic control.
Maltitol is one of the most absorbed and metabolized disaccharide polyols, which is relevant both to its caloric yield and to its blood glucose raising potential relative to other polyols.
6. Body Systems and Health Areas of Association
- Metabolic / endocrine system: Maltitol is more slowly absorbed than sucrose, a property considered desirable for diets for people with diabetes. Its reduced, though non-negligible, glycemic and insulinemic responses place it in the category of low-GI sweeteners.
- Oral health: Maltitol- and xylitol-containing chewing gums significantly reduced gingivitis scores compared with a placebo gum in individuals who refrained from brushing. They were also shown to increase plaque pH and reduce plaque scores and levels of caries-associated bacterial species from the genera Streptococcus, Lactobacillus, and Actinomyces.
- Gastrointestinal system: Most polyols, including maltitol, have side effects when overeaten, such as laxative effects, gastrointestinal symptoms, bloating, diarrhea, and abdominal pain. Polyols can induce dose-dependent symptoms of flatulence, abdominal discomfort, and laxative effects when consumed by both healthy volunteers and patients with IBS.
- Gut microbiota: Maltitol is partially degraded by gut flora into volatile fatty acids, which are easily absorbed and utilized by the microbiota. Limited human evidence points to a possible prebiotic increase in bifidobacteria and lactobacilli.
- Cardiovascular / metabolic risk (indirect): Consumption of a low glycemic index diet may be helpful in the management and prevention of diabetes and cardiovascular disease, and maltitol's low-GI classification is sometimes invoked in this context, though no dedicated cardiovascular outcome trials for maltitol exist.
7. Dosage Forms and Dosages Reported in Studies
Maltitol is not used as an isolated supplement at defined therapeutic doses; rather, it is consumed as a component of food products. The following dosage figures are those reported in human studies:
- Glycemic and insulinemic response studies typically used 50 g of maltitol dissolved in 150 ml of mineral water, administered after an overnight fast.
- In digestive tolerance and glycaemic response research, maltitol was consumed in chocolate dairy desserts at a dosage of 35 g in mixtures with other sweetener components.
- An optimal dose of 34.2 g for maltitol plus polydextrose (combined) was used to observe significant increases in faecal bifidobacteria, lactobacilli, and short-chain fatty acids.
- In a laxative threshold study, the mean threshold dose for occasional maltitol consumption was 92 ± 6 g/day before symptoms became severe.
- In another design, osmotic diarrhea appeared at doses of approximately 90 g and transitory osmotic diarrhea at a dose of 45 g.
- It has been noted that maltitol has excellent digestive tolerance up to 50 g/day, a level at which most healthy individuals do not report significant symptoms.
- Typical practical recommendations suggest not exceeding 0.3–0.8 g per kg of body weight daily, though this range does not derive from a single established regulatory guideline but rather from review of tolerance data.
8. Regulatory Status
In the United States, the Food and Drug Administration (FDA) accepted a petition affirming its Generally Recognized as Safe (GRAS) status in 1986 for applications in candy, chewing gum, and confections, with expansions in 1995 to include broader uses as a sugar alcohol.
In the European Union, maltitol is authorized as food additive E965 under Regulation (EC) No 1333/2008, permitted at levels up to quantum satis (as needed) without an acceptable daily intake (ADI) limit, reflecting its safety for unrestricted use in authorized categories.
The Joint FAO/WHO Expert Committee on Food Additives (JECFA) established an ADI of "not specified" in 1993, indicating no safety concerns at levels consistent with good manufacturing practices.
The European Union's Scientific Committee on Food (SCF) and the JECFA reviewed safety data for maltitol at multiple meetings. The studies evaluated included multiple genotoxicity studies and acute, subchronic, and chronic toxicity studies in mice, rats, and dogs, as well as an embryo-fetal development study, a multi-generation reproduction/development study, and two-year carcinogenicity studies in rats. Concluding that maltitol is safe, the SCF and JECFA assigned their safest category of an ADI of "not specified."
Maltitol and maltitol syrups have been assigned E number E965 and are approved for use in food at quantum satis for a variety of food items specified in the regulations, usually bakery goods, confectionery, ice cream, desserts, and fruit preparations.
Maltitol is generally recognised as halal, is kosher pareve as it meets all kashruth requirements, and is regarded as vegan-friendly; it is also GMO-free because raw material starch comes from non-GMO plants.
9. Safety Considerations and Adverse Effects
9.1 Gastrointestinal Effects
Compared to the reactions that occur after consuming standard sucrose-containing chocolate, the occasional or regular consumption of increasing doses of maltitol is not associated with significant digestive symptoms at moderate doses, but does result in increased diarrhea at higher doses.
If any food product contains more than 10% added maltitol or other polyols, it must include the statement "excessive consumption may have laxative effects" in the EU.
A dose-dependent relationship for gastrointestinal symptoms has been seen with isomalt, lactitol, and maltitol, consistent with the class effect of polyols.
9.2 Effect in Individuals with IBS
Polyols can induce dose-dependent symptoms of flatulence, abdominal discomfort, and laxative effects when consumed by both healthy volunteers and patients with IBS; further research is needed to better understand the effects of specific polyols on gastrointestinal function, sensation, and the microbiome in gastrointestinal disorders such as IBS.
In patients with IBS, symptom provocation has also been shown to be dose-dependent, although the dose-response curve appears to be shifted to the left, presumably as a consequence of underlying abnormalities in motility, transit, and visceral sensation.
Even in smaller amounts, maltitol may cause issues for individuals with sensitive digestion, especially those with Small Intestinal Bacterial Overgrowth (SIBO).
9.3 Glycemic Concerns in Diabetes
Maltitol has a reported glycemic index of 35, which is significantly higher than other polyols like erythritol or mannitol (GI of 0), resulting in a notably higher impact on blood sugar that can potentially cause spikes in individuals with diabetes or insulin resistance.
Unlike erythritol, maltitol is partially absorbed in the small intestine and contributes directly to blood glucose levels. This distinguishes it meaningfully from zero-GI polyols and is a clinically relevant consideration for individuals counting carbohydrates or managing insulin dosing.
9.4 Caloric Contribution
When consumed excessively, maltitol still contributes to energy intake and, therefore, to weight gain. Although it has a lower caloric value than sugar, maltitol still provides energy; consuming it frequently and in large quantities (e.g., in "low sugar" sweets) can contribute to excess calories just like other carbohydrates.
9.5 Potential Cardiovascular Concern at Very High Doses
The accumulation of maltitol may lead to amplified levels of extracellular fluid, which may cause asymptomatic heart failure at very high intakes, though this is considered a theoretical risk associated with extreme consumption rather than typical dietary exposure.
9.6 Labeling and Consumer Awareness
Most jurisdictions require foods that may contain more than 10% added polyols to carry a statement about potential laxative effects.
Depending on the overall formulation, products containing maltitol can display a number of label claims, including "no sugar added," "sugar-free," and "low-calorie."
9.7 Genotoxicity
Maltitol is considered non-genotoxic and may have mild prebiotic effects, promoting the growth of beneficial gut bacteria like bifidobacteria.
The multi-species toxicology program reviewed by both the SCF and JECFA, including two-year carcinogenicity studies, identified no safety concerns at levels consistent with normal food use.
10. Summary of Evidence Quality
The body of human clinical evidence on maltitol is moderate in volume but limited in depth. The most robust evidence pertains to its non-cariogenic properties (multiple randomized trials in children and adults) and its reduced glycemic and insulinemic responses compared to glucose (several crossover trials, consistent across ethnicities). The evidence for prebiotic effects is preliminary and confounded by multi-ingredient study designs. No long-term randomized controlled trials have examined maltitol's effects on hard clinical endpoints such as caries incidence rates, type 2 diabetes outcomes, body weight, or cardiovascular disease. Regulatory bodies in the US, EU, and internationally have independently reviewed the safety evidence and assigned the most permissive safety classifications available, supporting its broad use in food products.
References
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