Study Finds Sorbitol Can Convert to Fructose, Raising Metabolic Concerns

Scientists at Washington University in St. Louis demonstrated that sorbitol, widely used in sugar-free candies and gums, is not inert; it can be metabolized into a fructose-related molecule in the liver. Experiments in zebrafish traced sorbitol’s pathway from the gut, where it can be generated from dietary glucose, to the liver, where conversion occurs. The presence of specific gut bacteria, notably Aeromonas strains, can degrade sorbitol and prevent its systemic absorption, but lacking these microbes allows sorbitol to reach the liver.

Excessive sorbitol intake—whether from large amounts of glucose-derived production or direct consumption—can exceed bacterial capacity, potentially promoting steatotic liver disease. The findings challenge the assumption that sugar-alcohols are metabolically neutral and suggest that alternative sweeteners may still pose health risks. The research was funded by NIH grants.