New study questions benefits of cutting out sugar entirely

A new study has raised questions about the long-term effects of completely removing sugar from the diet, suggesting that extreme restriction may not always lead to better metabolic outcomes and could, in some cases, disrupt key biological functions.

Researchers presenting findings at ENDO 2026 in Chicago reported that a sugar-free diet in animal models was linked to unexpected negative changes in metabolic health, despite no significant differences in body weight between groups.

The study, conducted by scientists at the Dasman Diabetes Institute in Kuwait, examined mice placed on a low-fat diet either with or without sucrose over a 16-week period.

While both groups maintained similar weight profiles, the mice fed a sucrose-free diet showed poorer blood sugar control and increased insulin resistance.

Researchers also observed signs of broader metabolic disruption, including changes in gut microbiota, elevated intestinal inflammation, and liver alterations associated with fatty liver disease.

Lead researcher Dr. Rasheed Ahmad said the findings highlight the importance of dietary balance rather than the strict elimination of specific nutrients.

He noted that completely removing sucrose may negatively affect gut bacteria, which play a crucial role in regulating metabolism and inflammation.

The study also points to a gap in existing research on the long-term effects of highly restrictive low-sugar diets, particularly in relation to gut and immune system health.

Scientists concluded that balanced carbohydrate intake may be important for maintaining metabolic stability and gut health, and suggested that future dietary guidelines should focus on overall nutritional quality rather than complete sugar avoidance.

They also emphasized that further research in humans is needed to determine whether the same effects observed in mice apply to people following similar diets.