How the Digestive System Works
When you eat, food travels from the mouth down the esophagus to the stomach. Then it moves through the small and large intestines, and eventually out through the anus as waste. The liver, pancreas, and gallbladder are also included in the digestive system. These organs produce chemicals that allow digestion to occur.
All of these organs work in harmony to make sure the body receives the nutrients it needs. Some of the organs are hollow, while others are solid. A series of muscle contractions moves food through the digestive system from the hollow organs to the solid organs. This important process is called peristalsis.
The hollow organs of the digestive system include the following:
Digestion starts in the mouth. This is where the action of chewing begins to break down starchy foods into carbohydrates. Special glands inside the mouth release saliva. Saliva and the enzymes present in saliva also help accelerate the breakdown of starchy foods.
This organ pushes food from the mouth down to the next part of the digestive system, the stomach.
Once food drops down the esophagus, the muscles at the top of the stomach relax to allow the food to enter. After the food goes into the stomach, the muscles at the bottom of the stomach begin to move. The movement combines the food with the acidic digestive juices produced by glands in the stomach. The acid primarily breaks down foods containing protein. Eventually, the contents of the stomach are emptied into the small intestine.
The muscles of the small intestine mix food with its own digestive juices, along with those from the pancreas and liver. As the small intestine pushes the food toward the large intestine, these digestive juices help to further break down the food into carbohydrates, fats, and proteins. The walls of the small intestine then absorb nutrients from the digested food and deliver them into the bloodstream. From there, the blood carries the nutrients to cells throughout the body.
Not all food is broken down by the digestive system. Waste, or undigested food and dead cells, is pushed down to the large intestine. The large intestine absorbs the water and remaining nutrients from the waste before transforming it into solid stool. Stool is stored at the end of the large intestine, called the rectum, until it’s expelled from the body during a bowel movement.
While the hollow organs play critical roles in the digestive process, the solid organs release various chemicals that allow the digestive process to actually work.
The solid organs of the digestive system include the following:
The pancreas is located in the upper part of the abdomen, behind the stomach. It produces digestive juices that help the small intestine break down food into carbohydrates, proteins, and fats. It also makes chemicals that help regulate blood sugar levels, which affect how much energy the body has available to use.
The liver is a very large organ located above the stomach in the upper abdomen. Among its many important functions, the liver creates bile, a digestive substance that’s stored in the gallbladder. During digestion, bile is sent into the small intestine to help break down foods that contain fats. Besides aiding in the digestive process, the liver also stores nutrients and helps remove toxins from the body.
The gallbladder is a small pouch that stores the bile made in the liver. During digestion, the gallbladder releases bile into the top part of the small intestine to break down foods that contain fats.
Maintaining Digestive Health
Keeping your digestive system healthy can help you avoid digestive problems. Follow these easy tips to keep your digestive system in tip-top shape:
- Eat seven or more servings of fruits and vegetables every day. Fruits and vegetables contain fiber, minerals, enzymes, vitamins and prebiotics that keep your digestive system healthy.
- Eat whole-grain breads, pastas, and cereals. Whole grains contain more fiber and nutrients than white “enriched” grain products and help your good colon bacteria flourish.
- Avoid processed meats, such as sausages and hot dogs, as they can cause problems with the digestive system. You should also limit your consumption of beef, pork, and lamb. These meats are most likely to carry bacteria that can harm the digestive system.
- Get enough calcium and vitamin D. You can prevent digestive problems by making sure you consume an adequate amount of calcium-rich foods and beverages, such as milk, tofu, and yogurt. Taking vitamin D supplements and safely increasing your exposure to sunlight can also help prevent digestive issues.
- Exercise regularly. Staying physically active can help maintain a healthy digestive system. Aim for 30 minutes of moderate to vigorous activity at least three days per week.