What are prebiotics?

• A. Non-digestible fibers that feed beneficial gut bacteria
• B. Live bacteria that colonize the gut
• C. Enzymes that digest proteins
• D. Vitamins that promote gut lining

Answer: (A)

Prebiotics are non-digestible fibers that feed beneficial gut bacteria. They travel through the upper digestive tract largely intact and reach the colon, where they are fermented by microbes such as Bifidobacteria and Lactobacilli. This microbial nourishment supports the growth and activity of these beneficial bacteria, leading to the production of short-chain fatty acids that help nourish colon cells, strengthen the gut barrier, and modulate immune function. They are not live bacteria themselves—that would be probiotics—nor enzymes that digest proteins, nor vitamins that promote gut lining. Common dietary sources include certain fibers like inulin and fructooligosaccharides, as well as resistant starches found in foods such as onions, garlic, bananas, and chicory.