Subclass of Carbohydrates

Sugar Alcohols

Polyols such as mannitol and inositol — gentle sweeteners and signaling sugars.

Overview

About Sugar Alcohols

Sugar alcohols, or polyols, are sugars whose carbonyl group has been reduced to a hydroxyl. The change is small and it costs them their reactivity: a polyol cannot caramelize, cannot participate in the Maillard browning reaction, and is not fermented by oral bacteria.

In plants they serve as osmotic-stress protectants and transport sugars. In use they divide neatly into two camps — the bulk sweeteners of sugar-free foods, and a small set of genuinely bioactive cyclic polyols.

Where Sugar Alcohols Occur

Widespread, with a few plants concentrating one heavily:

Manna ash and seaweeds

mannitol

Birch bark, corn cobs and many fruits

xylitol

Rowan berries and stone fruit

sorbitol

Fermented fruit, and produced industrially

erythritol

Citrus, cantaloupe and beans

myo-inositol

Pine, soy and Bougainvillea

D-pinitol

Inositol is the outlier that justifies this page: chemically a cyclic polyol, biologically a second-messenger precursor with a genuine clinical literature.

Pharmacological Importance

Mannitol has a real place in hospital medicine as an osmotic diuretic, used intravenously to reduce raised intracranial and intraocular pressure. Xylitol's non-fermentability by Streptococcus mutans is the basis of its well-supported anticaries effect in chewing gum, which is a genuine dental-health intervention rather than a marketing claim.

Myo-inositol and its D-chiro isomer have accumulated real trial evidence in polycystic ovary syndrome — improving insulin sensitivity, ovulation rate and androgen profile — and at high doses in obsessive-compulsive and panic disorders. D-pinitol is a methylated inositol with insulin-sensitizing signals of its own.

Toxicity & Safety

The bulk polyols are poorly absorbed and osmotically active, so the dose-limiting effect is predictable and universal: they draw water into the bowel and are fermented, producing bloating, cramping and a laxative effect. Sorbitol is the worst offender and erythritol — largely absorbed and excreted unchanged — the mildest. They are also FODMAPs and problematic in irritable bowel syndrome.

Two specific points are worth carrying. **Xylitol is acutely toxic to dogs**, triggering profound insulin release and hypoglycaemia and, at higher doses, liver failure; sugar-free gum left within reach is a genuine veterinary emergency. And erythritol, long treated as inert, has recent observational and mechanistic work associating higher circulating levels with thrombotic cardiovascular events — not settled, but no longer ignorable.

Constituents

All Sugar Alcohols

7 total Filter sugar alcohols

Cordycepic acid 1 herb

d-pinitol 1 herb

Inositol 1 herb

Mannitol 1 herb myo-inositol 1 supp

Pinitol 2 herbs

Quercitol 1 herb

Open in filterable index

Source Plants

Herbs Containing Sugar Alcohols

6 herbs

Plants in the materia medica documented to carry sugar alcohols, with the compounds each one is listed for. The bar counts how many DISTINCT sugar alcohols are on record for a plant, relative to the best-documented — it measures breadth of record, not potency, so a plant with one well-studied compound can outrank a richer source that has simply been analysed less. No concentration figures are on record for this class yet, so nothing here distinguishes a major source from a trace.