The digestive process involves more than half a dozen organs from the mouth to the anus, along with a variety of enzymes, that assist in converting the food components you eat into usable nutrients for your body. The entire digestive process takes about 30 to 40 hours from consumption to excretion, according to the Colorado State University Extension. Digestive health maintenance, through proper diet and weight maintenance, is essential in order to avoid intestinal problems such as indigestion.
Mouth to Esophagus
The first step of digestion occurs when the teeth chew and grind up food into small pieces that form a ball-shaped bolus, which makes the food easier to swallow. While in the mouth, salivary glands release an enzyme known as salivary amylase, which digests the carbohydrates in the food being chewed. The bolus of food is then swallowed and transported to the esophagus, a long, tubelike tract of hollow organs that use downward muscular contractions, or peristalsis, to transport the bolus of food to the stomach.
In the Stomach
Once in the stomach, food boluses are further digested by a variety of digestive enzymes found in the stomach such as pepsin, which digests proteins, and lipase, which digests fats. According to the National Digestive Diseases Clearinghouse, the amount of time food particles remain in the stomach depends on how long they take to be digested. Carbohydrates spend the least amount of time in the stomach, proteins spend a little more time, and fats spend the most time in the stomach. As the digested food particles are transported to the small intestine, the digestive juices of the liver and pancreas are mixed with the food. The pancreas releases enzymes that digest fat, carbohydrate and protein particles in the food, while the liver produces bile, which is stored between meals in the gallbladder and released through bile ducts at mealtime.
In the Intestinal Tract
The small intestine is where a majority of the digestion and absorption of nutrients took place. Once in the small intestine, digested nutrients are absorbed through the intestinal walls through tiny, fingerlike projections on the intestinal lining known as microvilli. The nutrients are then transported to the bloodstream, to the liver, and delivered throughout the body. Undigested parts of the food, known as fiber, as well as older cells that have been shed from the mucosal lining of the small intestine are pushed into the large intestine, or colon, where they become a part of solid feces. Water from the food particles is reabsorbed back into the body while the feces are moved into the rectum to await excretion.
Suggestions for Digestive Health
Digestive conditions such as indigestion, gastroesophageal reflux disease, or heartburn can cause symptoms such as fullness and pain in the abdominal region, painful burning in the chest, as well as nausea and bloating. In order to treat or prevent such conditions, consume small, frequent meals, limit intake of fatty foods, refrain from smoking, get adequate sleep, find ways to keep stress levels down, and limit intake of caffeinated beverages such as coffee and cola.