Human Digestion: Fiber & Protein

The Mouth
An individual begins the digestion process by consuming a portion of food or liquid, regardless of how large or small the amount. The food is prepared and people begin to smell and see the food, which makes them desire to eat because of the salivary glands. Food is inserted into the mouth by a utensil or fingers and moistened by saliva. The tongue tastes the food, the food is chewed by the teeth, and finally the food is broken down and transformed into a substance called bolus.

The Throat & Stomach
The transformed food called bolus leaves the mouth and is swallowed into the pharynx, which is located in the throat. The bolus leaves the pharynx and enters the esophagus. The esophagus is a passageway from the pharynx to the stomach and has several muscles that contract. The epiglottis is an important organ that prevents food from entering the lung passageways. The bolus enters the stomach and is mixed with acids that change the bolus into a substance called chyme. Chyme begins to partially digest in the stomach within two to six hours, depending on the person and portion of food ingested.

Small & Large Intestine
The small intestine absorbs nutrients from foods and stores them in the body. The small intestine is divided into three parts; duodenum, ileum, and jejunum. The liver allows the secretion of bile which is essential for fat absorption and digestion. The gallbladder works with the liver by storing the bile produced. The pancreas secretes enzymes and bicarbonate into the small intestine to also assist in absorption and digestion of food. The food that is not digested and absorbed in the small intestine is passed into the large intestine though a sphincter. Water and vitamins are absorbed in the large intestine. The colon and rectum are also a part of the large intestine. The food not absorbed in the small or large intestine is carried into the colon. The colon pushes the materials into the anus which eliminates them from the body which is known as feces.

Soluble & Insoluble Fiber
The American Heart Association Web site states fiber is an essential part of an individual's diet. (1997, Horn). Consuming fiber helps to maintaining a healthy digestive system. Dietary fiber is based on insoluble and soluble fruits, vegetables, beans, legumes, whole-grains, and fortified foods.
Insoluble fiber sources have been proven to help lower blood cholesterol. Soluble fiber products are a great source of relieving sufferers of frequent constipation. Both fiber sources effectively help maintain health and should be an important aspect of people's diets. Foods with high amounts of insoluble fiber include; wheat cereals, wheat bran, rye, rice, cabbage, barley, carrots, beets, apple skin, turnips, and other grains. Foods with high proportions of soluble fiber include; strawberries, barley, peas, oatmeal, beans, rice bran, and citrus fruits.

Functions
Insoluble fiber moves heavy and bulky materials through the small and large intestines. Often people suffer with constipation and turn to consuming fiber sources in order to relieve their symptoms. Insoluble fiber also controls and balances the acidity within the intestines as well as prevents colon cancer. Soluble fiber helps lower blood cholesterol and regulates high or low blood sugar levels for people suffering with diabetes or hypoglycemia. (2005, Tsang). Both fibers have benefits and should be evenly consumed on a daily basis.

Children & Adults
According to the Fiber, Lipids, and Coronary Heart Disease article, children older than two years old should reduce saturated fat intake to thirty percent and ten percent of total calories. Apparently children need to get most of their calories from complex carbohydrates. Adults that consume fifteen-hundred calories or more each day should include twenty-five to thirty grams of fiber. The article does not suggest supplementing soluble or insoluble fiber with vitamins or medications because they don't now adequately serve the purpose of raw fiber. (1997, Horn).

Protein & Athletics
Protein enzymes found in certain foods are broken down and composed of amino acids that are essential nutrients for the body. Athletes, trainers, coaches, and body builders focus to load up on protein and amino acids because it's believed that excessive protein consumption improves strength, agility, performance, and muscle mass. Often people increase their protein intake by eating less fattening foods and base their diet on high protein foods that include fish, tuna, chicken, peanuts, and much more. Protein and power bars are loaded with protein and may substitute a snack or meal. There are also protein shakes and pills on the market that athletes can buy to increase their protein.
Why is it believed that increasing protein intake will help athletes become faster, stronger, and better? According to the article, "But a growing body of research has found no evidence that increasing protein intake - and particularly consuming specific amino acids through supplements - has any relation to fitness." (1988, Stockton). The article also stresses excessive protein intake can cause harm to major organs and the digestive system. Sometimes amino acid overload will cause kidney functions to fail and the digestive track to become blocked. It's also possible that amino acids aren't always absorbed properly because there are too many in the body.
Eating a healthy and well-balanced diet is proven to help people improve their overall well being and performance. The article says a male who weighs 180 pounds needs 66 grams of protein per day. Finding out how much a person needs of protein on a daily basis requires no more than a discussion with a health professional or resources from the Internet. Following dietary guidelines of protein and other essential nutrients will help better in athletics than loading up on protein.

References
Horn, L. PhD, R.D. (1997). Fiber, Lipids, and Coronary Heart Disease. American Heart Association. Retrived December 13, 2006 from http://circ.ahajournals.org/cgi/content/full/95/12/2701
Stockton, W. (1988). Fitness; It may not be exciting, but you'll perform best with a balanced diet. New York Times. Retrieved January 4, 2007 from ProQuest database.
Tsang, G. R.D. (2005). Soluble Fiber vs. Insoluble Fiber. Health Castle. Retrieved December 13, 2006 from http://www.healthcastle.com/fiber-solubleinsoluble.shtml