Slow release

Why is isomaltulose digested more slowly?

The slow-release properties of isomaltulose originate from its molecular structure. Sucrose and isomaltulose are both made of glucose and fructose, but the bond between these two molecules is different.
Sucrose contains an α-1,2 glycosidic bond, whereas isomaltulose contains an α-1,6 glycosidic bond, which is more stable and is hydrolyzed more slowly by enzymes in the small intestine. Enzyme kinetic studies show that isomaltulose is broken down approximately four to five times more slowly than sucrose. As a result, glucose enters the bloodstream more gradually, leading to a lower and more sustained postprandial blood glucose response

Metabolic response to slow release

Because isomaltulose is digested and absorbed more gradually, it produces a different postprandial metabolic response than rapidly available carbohydrates. Human studies have shown that isomaltulose can lead to:

• Lower postprandial blood glucose peaks
• Reduced insulin responses
• A more sustained glucose supply over time
• Higher fat oxidation in specific study settings

This profile helps explain why isomaltulose is relevant for nutrition strategies focused on glycemic response, sustained energy and metabolic health.

Incretin hormone response

The slower digestion and absorption of isomaltulose also influence incretin hormone responses. Compared with sucrose, isomaltulose has been shown to stimulate higher glucagon-like peptide-1 (GLP-1) release and lower glucose-dependent insulinotropic polypeptide (GIP) release in specific human studies.
This difference is related to the slower hydrolysis and more distal absorption of isomaltulose in the small intestine. As less glucose becomes available in the upper small intestine, stimulation of GIP-secreting K cells is reduced, while carbohydrate absorption further along the small intestine results in greater stimulation of GLP-1-secreting L cells. This incretin profile may help explain some of the observed differences in postprandial blood glucose and insulin responses compared with sucrose.

Slow-release carbohydrates offer a different metabolic profile from rapidly available carbohydrates. Rather than supplying glucose rapidly, slow-release carbohydrates provide carbohydrate energy more gradually over time. For isomaltulose, this slow-release profile is relevant to several areas of nutrition science, including:

• Blood glucose management
• Sustained energy
• Fat oxidation
• Sports nutrition
• Weight management
• Metabolic health