Sugar Alcohols (Polyols)

KEY Fermenters: Oxidation or fermentation by gut bacteria producing acid; Use: Utilisation or assimilation by gut bacteria; Common: Combined use and O/F for widespread, moderate and minor gut colonisers (total bacteria: 500);

Polyols Common users All users Common fermenters All fermenters Example users Prevalence in Food Human digestion, metabolism, interactions Structure
Adonitol 5 49 14 67 Citrobacter koseri; Eubacterium limosum; Lacrimispora saccharolytica; Megasphaera elsdenii; Serratia marcescens; Rare sugar. From yeast fermentation Detectable in urine of healthy people but elevated levels indicate a yeast infection Adonitol
D-Arabitol 7 60 16 90 Citrobacter koseri; Clostridium beijerinckii; Eubacterium limosum; Klebsiella grimontii; Klebsiella oxytoca; Klebsiella pneumoniae; Klebsiella quasipneumoniae subsp. quasipneumoniae; Found in sweet potato and chestnuts May accumulate in the body in cases of ribose-5-phosphate isomerase deficiency or transaldolase deficiency D_Arabitol
L-Arabitol 3 18 7 34 Clostridium beijerinckii; Enterobacter hormaechei subsp. hormaechei; Serratia marcescens; Fount in sweet potato, deerberry, moth bean, and European chestnut Made by NADH reduction of arabinose or lyxose and is found in most biofluids L_Arabitol
Dulcitol 5 34 14 67 Clostridium beijerinckii; Clostridium disporicum; Enterobacter hormaechei subsp. hormaechei; Kosakonia cowanii; Terrisporobacter glycolicus; Foods containing galactose readily yield galactitol (dulcitol) once digested Deficiencies in aldose reductase can lead to accumulation of galactitol (reduced form of galactose) Dulcitol
Erythritol 1 32 8 33 Eubacterium limosum; Found in grapes, mushrooms, pears, watermelon and fermented foods. Also used as a sugar substitute Not digestible by humans. Can be absorbed, but is excreted unchanged in the urine. Due to osmotic effects, excess consumption can lead to diarrhoea. Few colonic bacteria are able do utilise or metabolise erythritol Erythritol
Glycerol 24 292 39 299 Bacteroides ovatus; Citrobacter farmeri; Citrobacter freundii; Citrobacter koseri; Desulfovibrio desulfuricans; Enterobacter asburiae; Enterobacter cancerogenus; Derived, after hydrolysis, from mono-, di- and triacyl glycerol-containing foods Digestible. Readily absorbed by the small intestine and is easily metabolised Glycerol
Inositol 15 151 23 124 Agathobaculum desmolans; Citrobacter koseri; Clostridium beijerinckii; Dorea longicatena; Enterobacter asburiae; Enterobacter cloacae; Klebsiella grimontii; As phosphatidylinositol, a component of some lecithins Digestible. myo-Inositol is made by the brain and kidneys in relatively large amounts Inositol
Mannitol 35 329 86 492 Acetivibrio ethanolgignens; Agathobaculum desmolans; Anaerobutyricum hallii; Anaerofustis stercorihominis; Blautia producta; Citrobacter farmeri; Citrobacter freundii; Widespread in vegetables (sweet potato, cauliflower) and fruit (watermelon, peaches). It is also used as a sweetner (sucrose replacement) Not digestible by humans. Mannitol is partially absorbed by the small intestine but remains essentially unmetabolised prior to excretion in urine. A mixture of mannitol, rhamnose and lactulose has been used to estimate small intestine permeability. The mixture is excreted essentially unchanged in the urine (Mahmood2007) Mannitol
Sorbitol 20 158 49 233 Citrobacter farmeri; Citrobacter freundii; Citrobacter koseri; Clostridium beijerinckii; Clostridium neonatale; Dorea longicatena; Enterobacter asburiae; Widespread in vegetables and fruit (apples, nectarines, pears and cherries) Digestible, although it can be malabsorbed like most polyols, and has been used as a laxative Sorbitol
Xylitol 2 34 9 42 Enterobacter hormaechei subsp. hormaechei; Serratia marcescens; Small amounts in plums, strawberries, cauliflower, and pumpkin Digestible, but is absorbed slower than sucrose. High consumption can cause diarrhoea. Absorbed xylitol is metabolised by the liver. About 50% of xylitol is used for energy generation (Livesey2014) Xylitol