Digestion

Digestion is a complex process by which the body breaks down food into absorbable nutrients, which are then used for energy, growth, and cell repair. This biochemical process begins in the mouth, where mechanical and enzymatic actions break down food into smaller particles. As food travels through the gastrointestinal tract, it undergoes further degradation: in the stomach, gastric acid and enzymes break down proteins; in the small intestine, enzymes from the pancreas and bile from the liver further dismantle fats, proteins, and carbohydrates; and in the large intestine, water and electrolytes are absorbed, with remaining waste prepared for excretion.

Nutrient absorption primarily occurs in the small intestine, where the inner lining is highly specialized with villi and microvilli to increase surface area. Glucose and amino acids are typically absorbed directly into the blood, while fatty acids and glycerol are absorbed into the lymphatic system. The circulatory system then distributes these essential nutrients throughout the body. Proper digestion is crucial for health, as it ensures the body receives necessary vitamins, minerals, and other compounds. Dysfunction in any part of the digestive system can lead to malabsorption, nutrient deficiencies, and a spectrum of gastrointestinal disorders.