ingestion

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ingestion

physiology

Also known as: drinking, eating

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June 29, 2026

Quick Summary

Ingestion is the process of taking substances into the body, primarily as food. This is the first step in digestion, which is the breakdown of food into smaller molecules that cells can absorb and use for energy and bodily functions.12

The digestive process begins in the mouth, where food is chewed and mixed with saliva, initiating the breakdown of carbohydrates. This mixture, called a bolus, is then swallowed, passing through the pharynx and esophagus to the stomach. In the stomach, gastric juices further break down proteins and fats, creating a semiliquid substance called chyme.34

Chyme then moves to the small intestine for further breakdown and nutrient absorption. Undigested material proceeds to the large intestine for water absorption, with waste eventually expelled from the body. The entire process typically takes 24 to 72 hours. Some cells can also ingest liquids through a process called pinocytosis.35

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digestion
Ingestion
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