How does the human digestive system actually work?

The digestive system breaks down food through mechanical and chemical processes. It starts in the mouth, where chewing and saliva begin breaking down carbohydrates. Food travels down the esophagus to the stomach, where acids and enzymes further break it into a liquid called chyme. This moves into the small intestine, where most digestion and nutrient absorption happens with help from the liver, gallbladder, and pancreas, which contribute bile and digestive enzymes. The small intestine's lining absorbs nutrients into the bloodstream. Remaining material passes into the large intestine, which absorbs water and electrolytes, compacting waste into stool. The rectum stores this waste until it's eliminated. The entire process typically takes 24 to 72 hours.