How common sweetener fructose uniquely paves way for obesity

Western diets, particularly American ones, often include high-fructose corn syrup or other forms of fructose as a cheap sweetener. Fructose, which is derived from many fruits and other plants, has been linked to a number of health risks by a growing body of research, and now a new study from Weill Cornell Medicine reveals how it may have this effect.

Past research has firmly established a link between increasing obesity rates across the world and the similar rise in fructose consumption, raising concerns about the potential risk of this sweetener to public health. How does fructose increase obesity risk?

The new study, which involved mice, revealed that diets high in fructose impact tiny structures in the small intestine called villi. These structures help the body pull nutrients from food during digestion — something that increases when someone eats a high-fructose diet.

According to the study, mice fed fructose diets experienced between a 25- and 40-percent increase in villi length in comparison to mice that didn't eat the high-fructose diet. The extra-long villi were linked to greater nutrient absorption in the mice, including dietary fat absorption.

The mice fed the high-fructose diet likewise experienced more fat accumulation and weight gain than the control mice. Unfortunately, this effect may also support the growth of intestinal tumors, building upon past research linking the sweetener to colorectal cancer.

The study's senior author Dr. Marcus DaSilva Goncalves explained:

Fructose is structurally different from other sugars like glucose, and it gets metabolized differently. Our research has found that fructose's primary metabolite promotes the elongation of villi and supports intestinal tumor growth.