NANP Board Practice Exam

Why are fructooligosaccharides considered prebiotic carbohydrates?

1. They break down in the small intestine and aid in digestion

2. They provide immediate energy to the body

3. They bypass degradation in the upper digestive tract and fuel beneficial flora in the large intestine

4. They are absorbed directly into the bloodstream

The correct answer is: They break down in the small intestine and aid in digestion

Fructooligosaccharides (FOS) are classified as prebiotic carbohydrates primarily because they bypass degradation in the upper digestive tract and reach the large intestine, where they serve as a food source for beneficial gut bacteria. This characteristic is crucial, as it facilitates the growth and activity of these beneficial microorganisms, promoting a healthy gut environment and potentially improving overall digestive health. The other choices discuss processes that do not align with the prebiotic definition. For example, breaking down in the small intestine would mean that FOS are absorbed before reaching the large intestine, which would negate their prebiotic effect. Providing immediate energy does not align with the role of prebiotics, as they are not intended for quick energy release. Lastly, absorption directly into the bloodstream pertains to nutrients that are digestible, unlike FOS, which are intended to nourish gut flora rather than being absorbed.