So what exactly does fiber do in your body? First, it might be helpful to understand what your colon does. Your colon’s main job is to complete the digestion process by removing excess water from food wastes that enter from the small intestine. If not enough water is absorbed, waste passes too quickly resulting in diarrhea-like symptoms. This also means that too much water being absorbed will lead to constipation.

Whereas protein, fats, and carbohydrates are almost entirely absorbed in the small intestines, fiber passes through the large intestine virtually unchanged. It does not provide your body with any energy or nutrients but is still critically important. Fiber basically helps keep food moving through the intestine and helps to expand the inside walls of the colon to ease the passage of waste. It does this by slowing the absorption of nutrients, absorbing water, and binding cholesterol. When you consume enough fiber, your body can absorb water which makes your stool larger and softer; this stimulates the intestinal muscles so less pressure is needed to expel the waste.

Fiber can also help with satiety (sense of being full), therefore preventing overeating. In addition, a high fiber diet helps promote healthy bowel activity and may help avoid some digestive disorders.

Sources: 10 Weeks to Wellness™, Paul Ratte, ND; Harvard School of Public Health; Jackson Gastroenterology