The Gut Flora
The digestive system contains a large number of micro organisms which are estimated to weigh over a kg. They are collectively called the Gut flora.The gut flora is acquired rapidly during and shortly after birth and is known to play an important role in determining the health of an individual.
It influences the metabolic activities of the gut and has considerable influence on the immune system. Some members of the micro flora may contribute to the body's requirements for certain vitamins, including biotin and vitamin B12. The gut flora includes both the beneficial organisms and the harmful ones that cause disease. There is no consensus of what constitutes an “ideal” intestinal micro biota but a healthy micro biota is thought to be one that contains high numbers of Lactobacilli and Bifidobacteria such that their activities predominate over other potentially harmful microbes.
B. The influence of the gut flora on health -
The bacteria in the gut fulfill a host of important functions, some of which are beneficial while others are harmful.
The beneficial effects include -
- Digestion of food and absorption of nutrients
- Stimulation of cell growth
- Suppression of the growth of harmful micro-organisms .
The harmful effects include –
- Intestinal putrefaction
- Production of carcinogens
- Gastrointestinal disorders such as diarrhea, constipation, IBS, liver damage etc
Thus for a state of good health it is important that the number of beneficial bacteria far outnumber the harmful ones.
Imbalance in the gut flora
To work efficiently our digestive system needs a healthy balance of intestinal flora where the number of beneficial bacteria outnumbers those that are potentially harmful.The normal gut flora can be thrown out of balance by a wide range of circumstances including -
- Indiscriminate use of antibiotics or other drugs, stress, disease, or exposure to toxic substances
- Too much fat or too little fiber
- Intensive travel
- Ageing
- Illness or infection
In such cases the beneficial bacteria may decline in number causing the potentially harmful ones that are a detriment to human health, to thrive. This results in disease and infection.
The Digestive System
The digestive system constitutes the second largest body surface, almost comparable in size to a tennis court. It is the largest organ of the human body with a length of approximately 7-8 meters. Although the primary function of the human digestive system has long been considered as digestion, absorption of nutrients and excretion of waste products, in recent years the role has changed. The different organs of the digestive system play an important role in the digestion of food and here is what they do -
The mouth - The digestive process begins in the mouth. Food is partly broken down by the process of chewing and by the chemical action of salivary enzymes (these enzymes are produced by the salivary glands and break down starche into smaller molecules).
The esophagus - After being chewed and swallowed, the food is pushed down this tube by powerful muscular contractions known as peristalsis which helps the food to reach the stomach from the throat. This muscle movement gives us the ability to eat or drink even when we're upside-down.
In the stomach - The stomach is a large, sac-like organ that churns the food and mixes it with a number of gastric juices including enzymes (which breaks down the proteins and starches) and acid which kills most of the bacteria that are present. This partly digested food is called chyme. Food can remain in the stomach for a few hours.
In the small intestine - After being in the stomach, food enters the duodenum, the first part of the small intestine. It then enters the jejunum and then the ileum (the final part of the small intestine). In the small intestine, bile (produced in the liver and stored in the gall bladder), pancreatic enzymes, and other digestive enzymes produced by the inner wall of the small intestine help in the breakdown of food. The nutrients can then be absorbed through the intestinal wall into the blood stream through tiny folds called villi and microvilli.
In the large intestine - When most of the nutrients have been absorbed, the remaining residue passes into the large intestine, which is home to over four hundred different species of bacteria. Some of these bacteria ferment undigested fibre and starch. Then water is removed and absorbed back into the body to create feces.
The Anus - The feces is then stored in the rectum until it is excreted via the anus.
The Pancreas - Although not a part of the digestive system the pancreas plays an important role in digestion.Just behind the stomach this gland secretes an alkaline juice which neutralizes the stomach acid and contains enzymes that helps to break down the food in the small intestine.
The Liver - The liver is the largest gland in the human body. The liver makes bile which helps to digest fat within the small intestine. Bile is secreted through a tube called the bile duct into the gall bladder.
The Gall Bladder - The gall bladder concentrates the bile and squeezes it into the small intestine where it emulsifies and helps to break down the fat.
