Here's why:

* Large Surface Area: The small intestine has a huge surface area due to folds, villi, and microvilli, which maximize contact with digested food.

* Blood Vessels: A dense network of capillaries runs throughout the small intestine's lining, allowing for efficient absorption of nutrients into the bloodstream.

* Digestive Enzymes: The small intestine produces enzymes that break down complex food molecules into smaller, absorbable units.

While some absorption occurs in the stomach, the majority of nutrient absorption happens in the small intestine.