Table 6 Metabolic fates of low-calorie sweeteners approved in the European Union (adapted from [107])
From: Biomarkers of intake for coffee, tea, and sweetened beverages
| Sweetener (CAS registry no.) | Metabolic fate | Route(s) of excretiona | References |
|---|---|---|---|
| Saccharin (81-07-2) | Not metabolised, excreted unchanged. | Urine | [109, 110] |
| Acesulfame-K (55589-62-3) | Not metabolised, excreted unchanged. | Urine | [108] |
| Aspartame (22839-47-0) | Hydrolysed to aspartic acid, phenylalanine and methanol. | N/A | [121, 122] |
| Cyclamate (139-05-9) | 80% of the population do not metabolise cyclamate. In 20%, it undergoes partial hydrolysis in the gut to cyclohexylamine. Extent of hydrolysis varies between and within individuals. | Faeces, urine | [113] |
| Thaumatin (53850-34-3) | Undergoes normal protein digestion. | N/A | [123] |
| NHDC (20702-77-6) | Metabolised by gut microflora to similar metabolites to naturally occurring flavonoids. | Urine | [124] |
| Salt of aspartame-acesulfame (106372-55-8) | Dissociates to individual sweeteners in digestive fluids and undergoes same metabolic fates. | See information for acesulfame-K and aspartame | [134] |
| Sucralose (56038-13-2) | Not metabolised, excreted mainly unchanged but 2% of absorbed portion excreted as conjugates. | Faeces, urine | [114, 115] |
| Steviol glycosides† | Bacterial hydrolysis in the gut to steviol which is then absorbed and excreted as steviol glucuronide. | Urine | [117,118,119] |
| Advantam (714229-20-6) | Converted to advantame acid and mainly excreted as such with 2 minor metabolites. | Faeces, urine | [120] |