To better understand gastroparesis, it helps to understand the anatomy of the stomach.
The esophagus is a muscular tube that propels food down to the stomach. The stomach is the most dilated portion of the digestive tube, situated between the esophagus and the beginning of the small intestine (duodenum). It lies in the upper central portion of the abdomen (above the umbilicus) and to the left of the midline. The stomach produces gastric juice (acidic), which serves to breakdown proteins.
The stomach slowly pushes the food into the small intestine (duodenum), which absorbs nutrients from the food. The food passes through the small intestine and into the large intestine, which absorbs water from the food. The small intestine is about 18 feet (3.5 m) long and the large intestine is about 5 feet (1.5 m) long.
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