From ChildrenWithDiabetes.com (https://archive.childrenwithdiabetes.com/d_08_b70.htm) :
Discovered in the 1960s, Isomalt is a mixture of two disaccharide alcohols: gluco mannitol and gluco sorbitol. Isomalt:
- is made from sugar
- is used in a variety of foods and pharmaceuticals
- provides the taste and texture of sugar
- is synergistic with other sweeteners
- provides, at most, 2 calories per grain
- does not promote dental cares
- does not increase blood glucose or insulin levels
Isomalt is a low digestible carbohydrate, which is only partially digested in the intestines. In the lower part of the intestinal tract, some of the non-absorbed portion is metabolized by colonic bacteria. These normal physiologic processes, which may, in some people, cause softer stools or more intestinal gas than usual, are similar to how the body responds to high-fiber foods. The few people who might be sensitive usually have no problem if they start with small portions and gradually increase their consumption of low digestible carbohydrates.
Extensive research has been conducted on the effect of Isomalt on blood glucose and insulin levels. This research shows that, after digestion of Isomalt, blood glucose and insulin values do not differ significantly from baseline levels in people who have either Type 1 or Type 2 diabetes.
From a Medical Study "Comparative study of isomalt and sucrose by means of continuous indirect calorimetry. Metabolism." by Thiébaud D, Jacot E, Schmitz H, Spengler M, Felber JP. (https://pubmed.ncbi.nlm.nih.gov/6381959/)
Unlike sucrose, whose ingestion was followed by significant changes in plasma glucose, insulin, and lactic acid during the first 60 minutes of the test, no significant changes in these parameters were observed following the administration of isomalt. The increase in CHO oxidation occurring between 30 and 150 minutes was significantly lower (P less than 0.01) following isomalt than after sucrose. Conversely, the decrease in lipid oxidation was significantly less (P less than 0.01) after isomalt in comparison to sucrose. It is concluded that the rise in CHO oxidation and in plasma glucose and insulin levels is markedly reduced when sucrose is replaced by an equal weight of isomalt. In contrast to other sugar substitutes, no increase in plasma lactic acid was observed after isomalt administration.
From a Clinical Trial "Improved metabolic control after 12-week dietary intervention with low glycaemic isomalt in patients with type 2 diabetes mellitus" by I Holub 1, A Gostner, S Hessdörfer, S Theis, G Bender, B Willinger, J Schauber, R Melcher, B Allolio, W Scheppach (https://pubmed.ncbi.nlm.nih.gov/19701877/)
Thirty-three patients with type 2 diabetes received a diet with foods containing 30 g/d isomalt instead of higher-glycaemic carbohydrates for 12 weeks.
After 12 weeks, significant reductions were observed for: glycosylated haemoglobin, fructosamine, fasting blood glucose, insulin, proinsulin, C-peptide, insulin resistance (HOMA-IR), and oxidised LDL (an atherosclerosis risk factor). In addition, significant lower nonesterified fatty acid concentrations were found in female participants. Routine blood measurements and blood lipids remained unchanged. The substitution of glycaemic ingredients by isomalt and the consequent on reduction of the glycaemic load within otherwise unchanged diet was accompanied by significant improvement in the metabolic control of diabetes.