The Organ That Completes the Digestion of Food

Digestion starts with the first bite.
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It's easy to forget about your digestive system until your stomach starts rumbling. The human digestive system is a tireless machine that works for hours after the last bite. From the teeth to the intestines, each organ plays a role in converting the food you eat into fuel for the body.


    The smell of baking cookies or a savory meal really does make your mouth water. The saliva produced by these delicious smells prepares your digestive system to kick into high gear. As soon as you take a bite, your teeth and saliva break down food. After swallowing, the food passes into your esophagus, a long tube that leads to the stomach.

    The teeth begin the digestive process.


    Your stomach contains powerful muscles that churn food into a paste-like substance for the small intestine. The inside of the stomach is a highly acidic environment, which allows for the breakdown of food. Heartburn is caused when stomach acid backs up into the esophagus. Common heartburn triggers are chocolate, spicy seasonings and fried foods. Occasional heartburn is not an issue, but frequent heartburn attacks can be a sign of a treatable chronic condition known as GERD, or gastroesophageal reflux disease.

    Heartburn is a backup of stomach acids.


    The food moves from your stomach to the small intestine. The term, small intestine, is a bit of a misnomer. Though narrow in diameter, the small intestine is between 20 to 25 feet long. As food passes through this winding structure, nutrients are absorbed. At the beginning of the small intestine, chemicals from the liver and the pancreas are added to the food. The pancreas produces chemicals that digest food and regulate blood sugar. The liver secretes bile, which digests fat and helps produce waste.

    The small intestine absorbs nutrients.


    After the nutrients have been absorbed, your food passes to the large intestine. The large intestine absorbs water from the food and eliminates the rest as waste. A high-fiber diet promotes regularity by adding bulk to stools. Women should strive for 25 grams of fiber per day. Whole grains, nuts, beans, seeds, fruits and vegetables are all good sources of fiber. If you want to boost your daily fiber intake, increase your consumption gradually to prevent digestive upset. Try adding a few grams each week until you reach 25 grams a day.

    High-fiber foods help digestion.

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