Sorbitol (/ˈsɔː(r)bɪtɒl/), less commonly known as glucitol (/ˈɡluːsɪtɒl/), is a sugar alcohol with a sweet taste which the human body metabolizes slowly.^[1] It can be obtained by reduction of glucose, which changes the converted aldehyde group (−CHO) to a primary alcohol group (−CH₂OH). Most sorbitol is made from potato starch, but it is also found in nature, such as in apples, other tree fruits, and berries.^[1][3]

It is converted to fructose by sorbitol-6-phosphate 2-dehydrogenase. Sorbitol is an isomer of mannitol, another sugar alcohol; the two differ only in the orientation of the hydroxyl group on carbon 2.^[1] While similar, the two sugar alcohols have different sources in nature, melting points, and uses.

As an over-the-counter drug, sorbitol is used as a laxative to treat constipation.^[4] It provides about half the sweetness of table sugar.^[1]

Sorbitol may be synthesised via a glucose reduction reaction^[5] in which the converted aldehyde group is converted into a hydroxyl group. The reaction requires NADH and is catalyzed by aldose reductase. Glucose reduction is the first step of the polyol pathway of glucose metabolism, and is implicated in multiple diabetic complications.