Xylitol Increases Serum Triglyceride in Normal but Not in a Type 2 Diabetes Model of Rats

Dear Editor:

Xylitol is widely used as a sugar substitute not only by people who are overweight or obese or who have diabetes and metabolic syndrome but also is used in numerous foods and food products. Recently, we reported in the Journal of Medicinal Food that xylitol significantly ameliorates most of the diabetes-related parameters in nondiabetic rats. ¹ However, the concentration of serum triglycerides was significantly increased in xylitol-fed rats compared with rat chow- and sucrose-fed rats. ¹

In another previous study, Otto et al. ² reported that the postprandial serum triglyceride level was significantly increased in a xylitol formula-consuming group compared with a fiber-free formula-consuming group of healthy human subjects.

Chandramohan et al. ³ investigated the effects of 3-hydroxymethylxylitol in a streptozotocin-induced model of rats; although they mentioned that 3-hydroxymethylxylitol significantly decreased serum triglycerides with other lipids, the data for triglycerides were not presented in their article.

A significantly higher level of serum triglycerides has also been found after feeding xylitol to healthy dairy cows. ⁴ Similar results have also been observed after the infusion of xylitol in healthy human volunteers in a very old study. ⁵

In a recent study, Amo et al. ⁶ reported that feeding of xylitol at 1 g/100 kcal of energy did not have any significant effect, but xylitol at 2 g/100 kcal significantly decreased the plasma triglyceride level in high-fat diet-fed rats, which are very similar to type 2 diabetic rats.

In a most recent investigation, we have found that although the serum total cholesterol and low-density lipoprotein-cholesterol levels were significantly decreased, the serum high-density lipoprotein-cholesterol and serum triglyceride concentrations were not affected at all by ad libitum feeding of 10% xylitol solution in a type 2 diabetes model of rats. Hence, the results of the above-mentioned studies and our recent findings suggest that the effects of xylitol on serum lipids may not be similar between normal and diabetic conditions.