Scientists Discover Hidden Health Concern Linked to Popular Sugar Substitute - Video

A sugar substitute may not always stay in the gut. New research suggests sorbitol can be converted into a fructose compound and reach the liver after digestion.

Published in Science Signaling, the study examined how sorbitol is processed in the body and gut bacteria influence its fate. Researchers used zebrafish and found that the intestine can produce it from glucose after eating.

Sorbitol is a sugar alcohol commonly used in sugar-free sweets, chewing gum. It is also naturally found in some fruits.

The researchers found that certain gut bacteria, including Aeromonas strains, can break down sorbitol into a harmless bacterial product. This may keep sorbitol in the gut.

However, when sorbitol levels become too high, these bacteria may not be able to process all of it. Large amounts of glucose can also increase sorbitol production.

When sorbitol reaches the liver, it can be converted into a fructose compound. This is important because fructose metabolism has been linked with liver fat accumulation and metabolic effects.

The findings suggest that the effects of sorbitol may depend not only on how much is consumed, but also on the types and amounts of bacteria present in the gut.

However, the research is still at an early stage. The experiments were conducted mainly in zebrafish, so the findings cannot yet show that sorbitol causes liver disease in humans.

The study also does not mean that normal amounts of sorbitol from fruit are harmful. Researchers need to determine how this pathway works in humans and whether commonly consumed amounts can affect liver metabolism.

Overall, the findings challenge the idea that sugar substitutes pass through the body without metabolic effects and highlight the role of gut bacteria in determining what happens to these compounds.

REFERENCE: Madelyn M. Jackstadt, et al.; Intestine-derived sorbitol drives steatotic liver disease in the absence of gut bacteria. Science Signaling, 2025; 18 (910) DOI: 10.1126/scisignal.adt3549