Nutrition - Schachar

Question 1

How does fiber cuase increased stool bulk?

Answer 1

Unabsorbed carbohydrates stimulate large bowel microlora. Well fermented fibers cause microbial growth and gas production. Poorly fermented fiber maintains physical properties and holds water. Both cause increase bulk in colon, which causes faster transit, which causes less water absorptino, improved efficiency of bacterial growth and overal increased stool bulk.

Question 2

What are prebiotics?

Answer 2

Prebiotics are food ingredients, particularly, certain dietary fibers or oligosaccharides that cannot be digested other than by some specific bacteria and are involved in selectively stimulating the growth and / or activity of good bacteria (i.e. probiotics) to benefit the health of the host.

Requirements:

1. Resistance to digestion
2. Hydrolysis and fermentation by colonic microflora
3. Selective stimulation of growth of one or limited number of bacteria
4. Beneficial health effects to the host.