Biomarkers used to assess the effect of dietary xylitol or sorbitol in the rat

Because sugar alcohols can be used as bulk sweeteners and their possible lower energy values, interest has increased. Sorbitol and xylitol are hydrogenated monosaccharides that have widespread application. Male Fisher-344 rats were fed semipurified diets containing glucose without or with either 10% or 20% sorbitol or xylitol for 8 weeks following a 4-week adaptation period. The addition of sugar alcohols decreased food efficiency and total body weight gain regardless of the type fed. The addition of sugar alcohols to the diets decreased liver glucose-6-phosphate dehydrogenase (G6PD) and malic enzyme (ME). However, rats fed either 10% xylitol or sorbitol or 20% sorbitol had higher levels of epididymal fat tissue G6PD and ME. Plasma glucagon levels were decreased with the addition of sugar alcohols; whereas, in plasma insulin and glucose there was little effect. Diets containing sugar alcohols decreased levels of plasma triglyceride and cholesterol. The addition of sugar alcohols to the diets increased plasma alkaline phosphatase levels. Dietary treatments had no effect on urine or adrenal norephinephrine and epinephrine, and urine dihydroxyphenylacetic acid and dopamine. The addition of sugar alcohols to the diets had more of a metabolic effect than the type of sugar alcohol fed.