Digestion and absorption

Digestion breaks food into smaller molecules that the body can absorb. Chewing physically breaks food apart, while digestive enzymes chemically break down large molecules. Absorption moves digested nutrients across a body surface into internal transport systems. In humans, much nutrient absorption occurs in the small intestine. Its folded lining and tiny projections provide a large surface area. Digestion and absorption are related but different: breaking down food is not the same as moving nutrients into the body.