Why does fiber help digestion?
Show answer & explanation
Answer: Adds bulk and speeds transit
Adds bulk and speeds transit ✓ — Correct! Dietary fiber is plant material our bodies can't digest. Insoluble fiber (from wheat bran, vegetables) adds bulk to stool and speeds intestinal transit, preventing constipation. Soluble fiber (from oats, beans) absorbs water forming gel, slowing digestion and helping you feel full. Fiber also feeds beneficial gut bacteria, which produce healthy short-chain fatty acids!
Kills harmful bacteria — Wrong. While fiber does support beneficial gut bacteria which can outcompete harmful ones, fiber itself doesn't kill bacteria. Its main digestive benefit is mechanical - adding bulk and regulating transit time through the intestines.
Absorbs excess stomach acid — Wrong. Fiber doesn't absorb stomach acid. Its benefits are in the intestines - adding bulk to stool, regulating transit time, feeding beneficial bacteria, and helping maintain healthy cholesterol and blood sugar levels.