The Vitamins

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Dr. Kenneth Walker

The Vitamins

                              QUESTION # 1

            Discuss the history of vitamins and their discovery?

            Dr. Kenneth Walker was a consultant surgeon in London. He has a neat simple and straightforward style that suits his purpose excellently.  "The Vitamins" is an extract from his research work, "Human physiology". It is written in his typical plain prose style. 

            In the beginning only five basic ingredients of food were known. People tried to include all these ingredients in food to make it a balanced diet.  In 1906 Sir F. Gowland Hopkins conducted some experiment on rats.  He kept these rats on a diet of pure proteins, fats, carbohydrates, salts and water but still they developed the signs of malnutrition.  It diverted the attention of scientists to another ingredient that was still not known.   This ingredient was needed to keep ones body perfectly healthy.  Later experiments discovered it and it was named as the vitamin.

            In 1906 a disease called scurvy invaded the ships of East India Company.  In order to combat this scourge, lemons and oranges were used, which are a rich source of vitamins.  Another disease, which is thought to be due to vitamin deficiency, is beri-beri.  It is characterized by weakness and even complete paralysis of legs associated with dropsy.

            The research on all these diseases solidified the existence of vitamins and their importance for human body.  The true nature of vitamins is still not completely known and researches are still going on.

Q. No. 2:         What are the main types of vitamins?

            The vitamins are divided in two categories.  This division is on the basis of their solubility in fats or in water.   The letters of the alphabet are employed to distinguish them. The fat-soluble vitamins are A, D, and E.  The water-soluble vitamins are B and C.

           The first fat-soluble vitamin is A.  It is found in cod-liver oil in large quantity. Its smaller amounts are present in butter and green vegetables.  Deficiency of this vitamin results in stunted growth and reduces the natural resistance offered by the body to invading organisms.  Its deficiency produces a dry condition of eye known as Xerophthalmia.

            The second fat-soluble vitamin is D. It is found in cod-live oil and in lesser amounts in other animal fats but is not present in vegetable oils.  Its absence from food interferes with the growth and calcification of bones and is the cause of rickets.  Rickets is cured by adding vitamin D to diet or by exposing the patient to sunlight because another major source of vitamin D is sunlight

            The main water-soluble vitamins are B and C.  Vitamin B is found in yeast and in the outer layers of rice and wheat.  Its absence causes beri-beri and pellagra.  Vitamin B actually contains six different substances of varying importance.

            The second water-soluble vitamin C is present in fresh vegetables, in germinating peas and beans and in some fruits especially in lemons and oranges.  It is important as anti-scorbutic vitamin.

            Still more vitamins are being discovered and their efficacy is also being elucidated.

Q. No. 3:         Discuss the reasons of rickets?

            Rickets is a disease characterized by softening and bending of bones.  During the research on rickets, two completely divergent theories were presented about its causes.  According to some investigators, it was purely a diet-deficiency disease.  They proved that it could by readily cured by adding a small quantity of cod-liver oil to diet of the patient. At the same time, some investigators believed that it was related to the physical environment of the patient because rickets almost always attacked children living in dark industrial cities and was quickly cured when they were brought into the sunlight.

            On further investigations, it was proved that the main cause was the deficiency of vitamins D and it can be obtained either by mouth or skin.  That's why rickets may be caused by shortage of vitamins D or by the lack of sunlight.

            Vitamin D is present in cod-liver oil and animal fats.  Similarly it can be obtained through sunlight that transforms a certain fat found in the skin to vitamin D.

            So  this disease can be cured in these two ways.

Q. No. 4:         What should be done to fulfill the deficiency of vitamins?

            Today we fully know the importance of vitamins and we also know that the use of alkalis in flour grinding and in the milling of rice is strongly helping in the destruction of vitamins found in different foodstuffs. The governments and authorities do not pay attention to it.  So people should take steps to rectify the situation by compensating the loss of vitamins by taking them in the form of tablets.  In this way the interests of the government, millers and masses will be secured at the same time.