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Dr. Casimir Funk, a Polish biochemist in 1912, put forth the theory that foods contained essential chemical substances that were vital to life. He coined the term ' Vitamines' referring to them as ' Vital amines ', or nitrogen compounds. It later turned out that some of these substances were not amines and the 'e' was dropped, yielding to the much used "Vitamin " later. Till date, 13 vitamins essential to health have been discovered. Only very small amounts -- a few milligrams or even fraction of milligrams -- of vitamins are needed to maintain good health. Vitamins are classified according to how they are absorbed and stored in the body. Vitamins A, D, E, and K are soluble in water. The body can store fat-soluble vitamins in the liver and fatty tissue. Since most water-soluble vitamins are excreted in the urine, they need to be consumed more often. Provitamins are substances that the body can convert into vitamins. Beta carotene and a steroid in skin, get converted by sun's rays into vitamin D used by the body. Vitamins are synonymous with health: There is a false notion that, if a little is a bit good, a lot has to be better. Dr.Tim Byers, Dean at the Colorado School of Public Health, challenged this idea recently at the American Association for Cancer Research Meeting where he retorted: " We now have direct evidence that a lot is no better. Infact, a lot is worse and can create health problems." There is no doubt the body needs a minimum amount of vitamins to function normally. Deficiencies in Vit.-C can lead to scurvy, and inadequate Vit.-D can cause the body deformities of rickets in children. Most of the people who take vitamins don't have any such problem like pernicious anemia or hemorrhagic disease. In fact, most of them are completely healthy and take vitamins not to treat sickness, but to prevent it. Reviewing his work of 30 years, on vitamins and cancer at the AAFCR Meeting, Byers opined that vitamins actually can't prevent disease. The 1996 Physician's Health Study in Canada, he pointed out , found no evidence to show that beta-carotene (the dietary form of vit-A ) prevents cancer. In 2009, the Phsicians' Health Study II, found that vit.-C and vit.-E had no protective effect either. Study after study showed that vitamins C, D, and E did not lower the risk of cancer. Byers even produced worrying data which suggested that (excess) vitamins might actually increase people's cancer risk. Two other randomised trials found that high doses of beta-carotene increased the risk of lung cancer in smokers. Another trial that studied 35,000 men in Canada and US, found a link between high doses of Vit.-E and prostrate cancer in men. That position was later echoed by the US Preventive Sciences Task Force. Dr. Eliseo Guallar of Johns Hopkins University, believes most of the risk is due to the use of doses above and beyond what the body actually requires. Water-soluble vitamins, such as vitamin C and the B-Complex vitamins, will simply be filtered by the kidneys and passed in the urine, once the blood levels rise above a certain threashhold. Fat-soluble vitamins, such as vitamin A, D, E and K, may pose more of a problem, accumulating in the soft tissues of the body and potentiates causing toxicity at higher doses. "Most vit.-E supplements are 400 IU, which is 20 times what you get with diet ", Dr.Gualler explains. That is also 20 times more than you really need. Research conducted by him at John Hopkins showed that the risk with vit-E followed a dose response. In other words, people taking higher doses have a greater risk of dying. Byer's problem on the other hand, is the people taking handfuls of vitamin supplements or incredibly high doses into single pills. In 2013, a series of articles in the " Annals of Internal Medicine ", showed that daily multivitamins did not lower peoples risk of developing heart disease or Alzeimer's. It let Guallar and his colleagues to write an editorial in the same issue titled, " Enough is enough: Stop wasting money on vitamins and mineral supplements." For well-nourished adults, Gualler says, "Vitamins are at best, ineffective; there is no magic vitamin pill that could decrease disease." Last but not the least, emphasis has to be laid on the intake of vitamin D that enables the body to absorb calcium and phosphorus, the main ingredients of bones and teeth. One essential form of vit-D [D3] gets synthesised when our skin is exposed to sunshine. |
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Dr. Tej K.Munshi, {Ex. Prof. in Applied Sciences}, Feedback at: tejmunshi@gmail.com Newyork, Phone No: 518-374-7036 |
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