Your stomach is an important part of your digestive system. It’s an elongated, pear-shaped pouch that lies across your abdominal cavity to the left, slightly below your diaphragm.

Depending on the position of your body and the amount of food inside it, your stomach is capable of alterations in size and shape. Your empty stomach is about 12 inches long. At its widest point, it’s about 6 inches across.

As an adult, your stomach has a capacity of about 2.5 ounces when empty and relaxed. It can expand to hold about 1 quart of food.

A baby’s stomach capacity grows quickly:

  • 24 hours old: approx. 1 tablespoon
  • 72 hours old: 0.5 to 1 ounce
  • 8 to 10 days old: 1.5 to 2 ounces
  • 1 week to 1 month old: 2 to 4 ounces
  • 1 to 3 months old: 4 to 6 ounces
  • 3 to 6 months old: 6 to 7 ounces
  • 6 to 9 months old: 7 to 8 ounces
  • 9 to 12 months old: 7 to 8 ounces

As you eat, your stomach fills with food and drink. If you continue to eat after your stomach is full, it can stretch, similar to a balloon, to make room for the additional food. Chances are, you’ll feel discomfort if your stomach is stretched beyond its normal volume.

Although your stomach will typically return to its regular size once it digests the food, your stomach will expand more easily if you overeat on a consistent basis.

When you eat and your stomach stretches to accommodate food, nerves send signals to your brain. At the same time, ghrelin, a hormone that triggers hunger, decreases. Together, these messages tell your brain to stop eating. It can take your brain up to 20 minutes to register these messages.

Your stomach is an important part of your digestive system. It stretches to accommodate food and drink. Although it’s unlikely that consistent stretching will make your empty stomach much larger, overeating too often can make your stomach stretch easier.