Quest Vitamins LTD, |
Why vitamin C and E supplementation is beneficialThe media recently presented headlines claiming that vitamin C and E supplements are not useful in the prevention of heart attacks or strokes. Quest feels it is necessary to "put the record straight". The study that prompted these headlines was fundamentally flawed: the dosages used were very small and not taken consistently (vitamin E at 400IU was administered every other day), the vitamin E used was synthetic and compliance was not verified. A closer look at the evidence suggests that, vitamin C and E are essential antioxidant nutrients that, when taken as research indicates, can help promote heart health. In the early 1990s, several large population studies showed significant reductions in cardiovascular disease in those who consumed vitamin C or vitamin E. The most widely reported study evaluated 11,348 participants over a 10-year period of time, finding that higher vitamin C intake reduced cardiovascular disease mortality by 42% (click here to view the study abstract). Data from an analysis of 9 research papers indicates that doses exceeding 700mg are associated with a 25% reduction in heart disease risk. The picture regarding vitamin E supplementation is complex. The likely efficacy of vitamin E supplementation is dependant on its form, synthetic or natural. Specific carrier proteins in the liver selectively bind to vitamin E and transport it through the blood to cells throughout the body; these carrier proteins only recognize a portion of synthetic vitamin E and ignore the remainder. Japanese researchers gave natural or synthetic vitamin E to young women to measure how much vitamin E actually made it into their blood. It took only 100 mg (149 IU) of natural vitamin E to produce blood levels that required 300 mg (448 IU) of synthetic vitamin E. An increasing number of scientists are questioning the wisdom of administering alpha tocopherol vitamin E by itself. There are 8 naturally occurring vitamin E compounds; Alpha tocopherol and gamma tocopherol are the two major forms of vitamin E in blood. Alpha tocopherol displaces gamma tocopherol; when alpha tocopherol is given without gamma tocopherol, the result is that alpha tocopherol itself can be neutralized by the peroxynitrite free radical, normally kept in check by gamma-tocopherol. Gamma-tocopherol has a role in protecting the protein part of LDL ("bad" ) cholesterol from oxidation; oxidised LDL cholesterol is thought to explain the link between cholesterol and heart disease.
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