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How long can the complete process of digestion take?

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Diagram of the human digestive system viewed from the front, showing and labeling organs including the mouth, teeth, tongue, salivary glands, pharynx, esophagus, liver, stomach, gallbladder, pancreas, large intestine, small intestine, appendix, rectum, and anus. — digestion The human digestive system as seen from the front.

The complete process of digestion typically takes between 24 and 72 hours. The exact duration depends primarily on the type of food consumed and an individual's digestive health.1

The process occurs in several stages:

Stomach: Food generally remains in the stomach for 2 to 4 hours, where it is broken down into a semiliquid substance called chyme. The rate of gastric emptying is influenced by the composition of the meal; for instance, fluids empty faster than solids, and fats can delay the process.12
Small Intestine: Over the course of 3 to 6 hours, nutrients are broken down further and absorbed into the bloodstream.1
Large Intestine: The final stage, involving the absorption of water and salts and the formation of feces, can take anywhere from 12 to 48 hours.1