Sugar Alcohols (Polyols)

Sugar alcohols, also called polyols, are a group of carbohydrate sweeteners that includes erythritol, xylitol, sorbitol, maltitol, mannitol, lactitol and isomalt. They differ in small-intestinal absorption, colonic fermentation, energy contribution and acute glycemic effect.¹ Those differences are evidence against treating every polyol as one fixed net-carbohydrate deduction.

What are sugar alcohols, chemically?

The word “alcohol” refers to chemical hydroxyl groups; polyols are not beverage alcohol. Some occur naturally in small amounts, and manufacturers also use them in reduced-sugar products. Their biological handling is compound-specific. Erythritol is largely absorbed from the small intestine and excreted unchanged, whereas other polyols can be only partly absorbed and can be fermented after reaching the colon.¹

On a US Nutrition Facts label, sugar alcohols are included within Total Carbohydrate and may appear as an indented sub-line. Under EU and UK rules, Carbohydrate includes polyols by definition, while Fibre is separate.⁵⁶⁷

What does human evidence show?

The available studies do not support replacing every polyol gram with one standard fraction:

Evidence	What it supports	What it does not establish
Geoffrey Livesey's review reported substantially different glycemic-index values among polyols.1	Individual compounds have different acute metabolic effects.	GI as an absorption percentage or gram deduction.
A six-person digestion study found differing absorption or digestion for sorbitol and maltitol.2	A fixed fraction should not be assumed across compounds.	A population-wide counting formula.
In a randomized crossover study, a 50 g erythritol dose did not raise glucose or insulin relative to water or sucralose in 20 healthy participants.3	An acute, compound-specific result under that protocol.	Long-term outcomes, every population or a universal full deduction.
A 2025 randomized trial found that label-derived net-carbohydrate values did not precisely predict glycemic impact across seven commercial products.4	Product-level label estimates have prediction limits.	A validated replacement formula for all products.

How do sugar alcohols affect net carb counting?

There is no FDA, EU, UK or clinical rule that automatically deducts half of maltitol, sorbitol, xylitol, isomalt or glycerin. A package may also combine several compounds under one polyol line.

• US label: start with Total Carbohydrate. Enter a polyol adjustment only when the counting method being followed defines it and the label supplies enough information.
• EU or UK label: start with Carbohydrate, which includes polyols but already excludes fibre. Never subtract Fibre again. Apply only an explicitly selected polyol adjustment.

If no applicable method defines an adjustment, leave it at zero rather than inventing a percentage. The net-carb calculator follows this explicit-adjustment approach.

Do sugar alcohols cause digestive side effects?

An unabsorbed fraction can retain water in the intestine or be fermented in the colon, which can produce gas, bloating or a laxative effect. The relevant dose differs by compound, product, serving pattern and person; the evidence does not justify one universal symptom threshold.¹ Product warnings and individual tolerance are more informative than a blanket cutoff.

Frequently Asked Questions

Do sugar alcohols have one standard net-carb deduction?

No. Polyols differ, products may contain mixtures, and regulators do not prescribe one universal deduction. Use an adjustment only when the counting method defines it and the label provides enough information.

Do you subtract polyols from an EU or UK label?

EU and UK Carbohydrate includes polyols but excludes fibre. A net-carb estimate may apply an explicitly selected polyol adjustment, but fibre must never be subtracted from that Carbohydrate value.

Can a polyol's GI determine how many grams to subtract?

No. GI is a measured glucose-response index, not an absorption percentage or gram-for-gram deduction.

Can sugar alcohols cause digestive symptoms?

Yes. Unabsorbed material can retain water or be fermented in the colon. The response depends on the compound, dose, product and person, so there is no universal symptom threshold.

See also: Net carbs · Total carbs · Glycemic index · Keto Glossary index

Learn how these numbers fit into your daily targets in calculating your keto macros, or scan sweetener options in the keto food list.

Works cited

1. Health potential of polyols as sugar replacers, with emphasis on low glycaemic properties — Geoffrey Livesey, Nutrition Research Reviews, 2003 https://pubmed.ncbi.nlm.nih.gov/19087388/
2. Digestion and absorption in the human intestine of three sugar alcohols — L. Beaugerie and colleagues, Gastroenterology, 1990 https://pubmed.ncbi.nlm.nih.gov/2379777/
3. Oral Erythritol Reduces Energy Intake during a Subsequent ad libitum Test Meal: A Randomized, Controlled, Crossover Trial in Healthy Humans — Fabienne Teysseire and colleagues, Nutrients, 2022 https://pubmed.ncbi.nlm.nih.gov/36235571/
4. Equivalent Glycemic Load and Insulinemic Responses Elicited by Low-Carbohydrate Foods: A Randomized Trial in Healthy Adults — Thomas M. S. Wolever, Kevin Miller, and Taylor Banh, Current Developments in Nutrition, 2025 https://pubmed.ncbi.nlm.nih.gov/41439105/
5. Food Labeling: Revision of the Nutrition and Supplement Facts Labels — U.S. Food and Drug Administration, final rule, May 27, 2016 https://www.federalregister.gov/documents/2016/05/27/2016-11867/food-labeling-revision-of-the-nutrition-and-supplement-facts-labels

Article history

1. August 23, 2026Replaced blanket polyol deductions with compound-specific evidence and US versus EU/UK label rules
2. August 19, 2026First published