Proper digestion leads to optimal absorption and assimilation of food nutrients and supports their effective use and distribution throughout the body. The foods and beverages we choose to eat and drink can assist or impede healthy digestio.
Proper digestion leads to optimal absorption and assimilation of food nutrients and supports their effective use and distribution throughout the body. The foods and beverages we choose to eat and drink can assist or impede healthy digestion. Millions of people suffer needlessly from chronic indigestion and constipation, when a change in dietary habits is often the primary answer to alleviating digestive problems. Understanding the basis of digestive and enzymatic functions is one of the first steps to improving your own digestion
How the Digestive System Works
PDF Diagram of the Digestive System
Imagine a thirty-foot maze-like passageway winding its way through the center of your body. This miraculous food transport system is your digestive tract. The digestive tract, also called the gastrointestinal tract, has numerous connecting points along its route where food is broken down into simpler chemical forms (nutrients) by specialized enzymes for the digestion and absorption of macronutrients (protein, carbohydrates and fats) and micronutrients (vitamins and minerals)
The Mouth, Pharnyx and Esophagus
The smell and sight of appetizing food is the first signal the digestive system receives to begin the amazing process of digestion. Even before the first morsel of food enters your mouth, the digestive juices start flowing. With the first bite, ptyalin, an amylase enzyme in saliva, begins the breakdown of carbohydrates into glucose. Chewing food well (some experts recommend 100 times per bite) promotes better digestion even before food enters the stomach where the greatest active chemical digestion begins. Stomach muscle contractions assist the digestive process by kneading the partially digested food while gastric juices containing hydrochloric acid (HCl), pepsin, rennin and water begin the protein-digesting process. Some fat, and to a lesser degree, carbohydrates (which have been converted to sucrose) are also partially digested at this phase of the digestive process. This potent mix of chemicals is so strong that the stomach's membrane lining secretes a protective mucous barrier to prevent these corrosive gastric juices from damaging the walls of the stomach. Without adequate mucosal protection, the stomach lining would be burned by the stomach's own acids, creating painful stomach ulcers.
Digestive activity in the stomach lasts anywhere from one to four hours per meal depending on the combination and amounts of food ingested. Liquids pass through the stomach most quickly; next comes carbohydrates, then proteins, and finally fats. The secretion of intrinsic factor is another important function of the stomach. This protein substance is absolutely necessary for the absorption of vitamin B12 during the next stage of digestion in the small intestine. The pyloric sphincter at the base of the stomach opens to release this mash of semi-digested food, called chyme, into the small intestine.
The Small Intestine
There is not too much that is "small" about the small intestine. In fact, this twenty-foot section of the digestive tract is charged with accomplishing a huge task the unlocking and absorption of micronutrients from macronutrients. The activity of enzyme function in the small intestine is supported by enzymes from the food we eat. Over the course of approximately three hours, the small intestine, with the aid of the pancreas, liver and gall-bladder, breaks proteins down into amino acids, carbohydrates to simple sugars, and fats to fatty acids.
As chyme enters the small intestine, the pancreas, nestled below the stomach, contributes alkaline pancreatic juices necessary for the successful completion of the digestive process. These juices contain numerous enzymes. If fats have been eaten, the gall-bladder releases the bile it has stored. Bile is produced by the liver and is not really an enzyme, but rather a fat emulsifier that separates fat into small droplets that pancreatic enzymes break down for absorption.
The small intestine is comprised of three sections, the duodenum, jejunum and ileum. Each of these sections absorb different nutrients through the intestinal wall. For example, calcium, vitamin A, thiamine and riboflavin are absorbed by the duodenum. The jejunum absorbs fats and the illeum absorbs vitamin B12.
The Large Intestine
Basically used as a holding tank for waste produced through the digestive process, the large intestine, also referred to as the colon, is largely an elimination organ, although vitamin K, water and some electrolyte minerals are absorbed in this final section of the digestive tract.
A great many bacteria live in the colon, some of them friendly and beneficial, and others, dangerous and destructive. Incompletely digested food substances can be absorbed by the body as toxins or feed noxious intestinal bacteria. Proper elimination of waste and bacteria from the colon is largely dependent upon a high fiber diet, since fiber binds toxins and aids their passage through the colon.
Eating fermented foods with live bacterial culture and supplementing the diet with probiotic formulations ensures the cultivation of healthy intestinal flora.
Tips for Better Digestion
PDF Table of Solube and Insolube Fiber Content of Major Food Groups
Enzymes: The Conductors of Life
The surge of public interest in enzymes has been sparked by the increased media coverage of scientific research into the benefits of enzyme therapy. The conversion of the food we eat into smaller, useable nutrient components is one of the functions of digestive enzymes, but enzymes also play a key role in virtually all of the body's systems. In addition to their therapeutic use for digestive disorders, enzymes are now widely used in the treatment of various types of blood clots, certain forms of emphysema, inflammatory disorders, immune system function and in the treatment of several congenital deficiency diseases.
Every normal function of every single cell in our body relies on enzymes. Their activity regulates the speed and efficiency of the body's metabolic functions. Enzymes are produced by living cells and are made up of protein molecules. Without going through a biochemical transformation themselves, enzymes function as catalysts for thousands of specific biochemical reactions, from digestion to the repair of damaged tissue.
Research has revealed thousands of different enzymes, each with a specialized function. Among their many functions, enzymes:
There are two categories of enzymes, including:
There are several kinds of digestive enzymes, all designed to digest different types of food. Four main types of digestive enzymes are:
Each of these enzymes will only break down the substance it was made to handle, like a key that will only fit one lock. Different types of amylase, for example, will break down specific sugars, such as sucrose. It is essential, therefore, to eat a variety of foods or use an enzyme supplement to obtain the full spectrum of enzymes.
Enzymes are present in raw, natural foods. Processed and refined foods are depleted of enzymes due to the heating methods used to prepare them, including canning, baking, frying and pasteurization. Without the presence of enzymes, efficient nutrient absorption is impossible.
Unsuspecting consumers do not realize that their pasteurized fruit juices are absolutely devoid of enzymes. Breakfast cereals, boasting oats, fiber and fruit content are frequently heat-processed as well, rendering them enzyme-free.
Enzymes are also depleted or destroyed by infectious agents, parasites, smoking, airborne pollutants, excess ultra-violet radiation and certain over-the-counter and prescription drugs. Digestive enzymes are epecially sensitive to the effects of stress.
Enzyme-deficient processed foods not only inhibit proper digestion; they tax the body's ability to function at an optimal level. Without enzymes all metabolic functions slow down, making the body more susceptible to disease.
The use of caffeine and other stimulants provides temporary energy because the nervous system and metabolism are stimulated, but the result is destruction of enzymes.
Because enzymes are needed to break down food substances, a lack of them often causes unassimilated protein, yeast cells, carbohydrates and fats to be reabsorbed into the bloodstream, causing numerous health problems. This is one of the causes of leaky gut syndrome.
Digestive enzymes can be replenished in two ways: by eating raw, natural foods and through enzyme supplementation. Raw food is the most ideal way to obtain enzymes, since these foods provide the very enzymes needed for their own digestion.
The more thoroughly food is digested before it reaches the small intestine, the less demand is placed on the body to produce enzymes. Chewing food well stimulates the digestive enzymes in saliva, so that food is already partially broken down before it reaches the stomach.
Eating food that contains enzymes saves the body from having to make enzymes, a process which depletes energy.
Studies have shown that eating fresh, raw fruits and vegetables can boost the body's enzyme supply and help fight degenerative diseases such as cancer and arthritis.
Breast-feeding is the best source of enzymes for babies. Mother's milk contains all the nutrients needed for a child's growth and development for the first six months. Commercial baby formulas lack enzymes, a deficiency of which can cause colic, allergies, fevers and infection.