Isomalt is a sugar substitute, a mixture of the two disaccharide alcohols. It is used primarily for its sugar-like physical properties. It has little to no impact on blood sugar levels, and does not stimulate the release of insulin.

Like most sugar alcohols (including the chemically similar maltitol), isomalt carries a risk of intestinal distress when consumed in large quantities (above about 20–30 g (1 oz) per day).

Isomalt is widely used for the production of sugar-free candy, especially hard-boiled candy, because it resists crystallization much better than the standard combinations of sucrose and corn syrup. It is used in sugar sculpture for the same reason.

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