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History of Vitamins

The value of certain foods in maintaining health was recognized long before the first vitamins were actually identified. In the 18th century, it had been demonstrated that the addition of citrus fruits to the diet would prevent the development of scurvy and in the 19th century, it was shown that substituting unpolished for polished rice in a rice-based diet would prevent the development of beriberi.

In 1906, it was found that foods contained necessary "accessory factors" in addition to proteins, carbohydrates, fats, minerals, and water. It was discovered in 1911 that the anti-beriberi substance in unpolished rice was an amine which is a type of nitrogen-containing compound. It was then proposed that this be named vitamine for "vital amine" which subsequently came to be applied to the accessory factors in general. It was later discovered that many vitamins do not contain amines. However, this term continued to be used but without the final letter "e" because of its widespread use.

In 1912, the hypothesis of vitamin deficiency was developed. It postulated that the absence of sufficient amounts of a particular vitamin in a system may lead to certain diseases. In the early 1900s, scientists isolated and identified the various vitamins through experiments in which animals were deprived of certain types of foods.

Earlier research conducted were to determine the optimum intake of vitamins based on their levels for prevention of deficiency state. Nowadays, studies are being done to determine the potential for specific vitamins to prevent and treat disease, as well as to enhance physical and mental health and performance.

How Vitamins Work?

In the human body, proteins, carbohydrates, and fats combine with other substances to yield energy and build tissues. These chemical reactions are catalysed, or accelerated, by enzymes produced from or assisted by specific vitamins. These chemical reactions take place in specific parts of the body.

Vitamins are organic compounds that the human body needs for growth, health and reproduction, and to maintain normal body functions. Some vitamins are essential for growth, repair and maintenance of cells in the body. Others control biological processes in the different cell functions. Vitamins are usually in the foods we eat. However, some can also be man-made. These synthetic vitamins generally work in the body in the same way that vitamins from natural sources do.

There are two groups of vitamins. One is fat-soluble and the other is water-soluble. Fat soluble vitamins are those found in the fatty portion of cells in the body. The body processes and stores them the same way it does fat. Fat-soluble vitamins are not absorbed by the body unless there is some form of fat present in the intestine. It is therefore best to take them after a meal. Vitamins A, D, E and K are fat-soluble vitamins.

Fat-soluble vitamins have highly specialized functions. The intestine absorbs fat-soluble vitamins and the lymphatic system carries them to the different parts of the body.

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Fat-soluble vitamins are also involved in maintaining the structure of cell membranes. They are also believed to be responsible for the synthesis of certain enzymes.

The body can store larger amounts of fat-soluble vitamins than of water-soluble vitamins. The liver provides the chief storage tissue for vitamins A and D, while vitamin E is stored in body fat and to a lesser extent in reproductive organs. Relatively little vitamin K is stored. Excessive intake of fat-soluble vitamins, particularly vitamins A and D, can lead to toxic levels in the body.

Water-soluble vitamins are found in the watery part of cells in the body. They are necessary for growth and maintaining life. They include the "B" vitamins (Thiamine, Riboflavin, Niacin, Vitamin B6, Vitamin B12), Biotin, Choline, Folic acid, Pantothenic acid, and Vitamin C.

When a person takes in more water-soluble vitamins than are needed, small amounts are stored in the body tissue and the excess is excreted in the urine. Because water-soluble vitamins are not stored in the body in appreciable amounts, a daily supply is essential to prevent depletion.

Many vitamins work together to regulate several processes within the body. A lack of vitamins or a diet that does not provide adequate amounts of certain vitamins can upset the body's internal balance or block one or more chemical reactions in the cells.

Vitamins And Disease

Recent research has suggested that carotenes, and vitamins C and E form part of the body's defence against free radicals. Free radicals are potentially dangerous substances produced naturally by the body or by cigarette smoke. Fruits and vegetables contain these vitamins and may reduce the risk of heart disease and some cancers which might be initiated by free radical damage.

How Much Of The Vitamins Do We Need?

The body requires different amounts of each vitamin because each of them has a different function. Each person will have a different requirement according to the age, sex, level of activity and state of health. Most people are able to meet their requirements for vitamins by eating a daily balanced diet.

However, certain groups of people may have higher requirements for specific vitamins. These are people who are suffering from illnesses, recovering from an illness, taking certain medications, smokers and pregnant women. They have to ensure that they eat foods rich in particular vitamins. Consumption of selected vitamin supplements is sometimes advised if their daily food intakes do no provide adequate amounts of these vitamins to meet their additional needs. Infants and young children are recommended to have supplements of vitamins A and D for at least two years to meet their growing needs.

Vitamin supplements have become popular and a few enthusiasts may be in danger of overdosing themselves in their pursuit of health. This is particularly the case with the fat-soluble vitamins which are not excreted but stored in the body. It is generally advisable to consume vitamin rich foods rather than vitamin supplements.

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Vitamins And The Athlete

For many people as well as for athletes, vitamin supplements are the frequently used nutritional supplements. Much of this use represents an expensive and wasted effort because daily balanced diets can meet the vitamin needs of most people.

Some athletes think that vitamin supplements help enhance their performance. However, there is little evidence that extra intakes of vitamins will improve performance unless a vitamin deficiency exists. They do not contain energy. They help the body use the nutrients to produce energy through chemical reactions in the cells. Many vitamins help maintain normal body tissue structure and repair. They act as a regulator and are needed in only very small amounts.

Some athletes supplement their diets without question. Using a simple multi-vitamin supplement that does not provide more than 100% of the daily requirement for any of the nutrients will most likely not be harmful. However, "super" supplements which is the consumption of large doses or megadoses, may be harmful to the body.

Some vitamins such as vitamins A and D can be stored in the body. Excesses of these vitamins can lead to undesirable side-effects such as headaches, and muscle and joint pains. Many of the vitamins also work in balance with each other. If one appears in a greater than normal amount, the other vitamins become unbalanced in supply. The advantage of getting vitamins by eating a variety of foods is that they usually come in balanced proportions.

Previous studies of the vitamin status of athletes compared to non-athletes showed no differences between the two groups. Supplementation with water-soluble vitamins improved blood levels but the improved levels did not enhance athletic performance.

As for the antioxidant vitamins such as vitamin E, vitamin C and beta-carotene, there is some concern that strenuous physical activity produces a stress that may require extra antioxidants. However, supplementation with these antioxidants does not consistently show that athletic performance will be improved. The taking of antioxidant supplements as an extra protection is controversial. Without question, athletes and those who exercise regularly should eat foods such as fruits and vegetables that are rich in antioxidants.

Conclusion

Vitamins are essential for growth, maintenance and reproduction of the human body. They are important for a normal appetite, in digestion, mental alertness and resistance to bacterial infections. In addition to satisfying the body's daily needs and preventing deficiency diseases, vitamins have several therapeutic effects. Niacin can be used to lower cholesterol and vitamin A can be used to treat acne. Large doses of vitamins may slow, or even reverse many diseases previously thought an inevitable part of ageing, such as cancer, heart disease, osteoporosis, impaired immunity, nerve degeneration and other chronic health problems.

A daily balanced diet can ensure adequate supply of vitamins to the body except in those whose daily requirement has increased such as those who are sick, taking certain medications, infants and pregnant women. High-dose vitamin supplements should only be consumed with caution.

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