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Query: UMLS:C0042875 (vitamin E deficiency)
 916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In this study the effects of vitamin E deficiency and supplementation on bone calcification were determined using 4-month-old female Sprague-Dawley rats. The rats weighed between 180 and 200 g. The study was divided in three parts. In experiment I the rats were given normal rat chow (RC, control group), a vitamin E deficient (VED) diet or a 50% vitamin E deficient (50%VED) diet. In experiment 2 the rats were given VED supplemented with 30 mg/kg palm vitamin E (PVE30), 60 mg/kg palm vitamin E (PVE60) or 30 mg/kg pure alpha-tocopherol (ATF). In experiment 3 the rats were fed RC and given the same supplements as in experiment 2. The treatment lasted 8 months. Vitamin E derived from palm oil contained a mixture of ATF and tocotrienols. Rats on the VED and 50%VED diets had lower bone calcium content in the left femur compared to the RC group (91.6 +/- 13.3 mg and 118.3 +/- 26.0 mg cf 165.7 +/- 15.2 mg; P < 0.05) and L5 vertebra (28.3 +/- 4.0 mg and 39.5 +/- 6.2 mg compared with 51.4 +/- 5.8 mg; P < 0.05). Supplementing the VED group with PVE60 improved bone calcification in the left femur (133.6 +/- 5.0 mg compared with 91.6 +/- 13.3 mg; P < 0.05) and L5 vertebra (41.3 +/- 3.3 mg compared with 28.3 +/- 4.0 mg; P < 0.05) while supplementation with PVE30 improved bone calcium content in the L5 vertebra (35.6 +/- 3.1 mg compared with 28.3 +/- 4.0 mg; P < 0.05). However, supplementation with ATF did not change the lumbar and femoral bone calcium content compared to the VED group. Supplementing the RC group with PVE30, PVE60 or ATF did not cause any significant changes in bone calcium content. In conclusion, vitamin E deficiency impaired bone calcification. Supplementation with the higher dose of palm vitamin E improved bone calcium content, but supplementation with pure ATF alone did not. This effect may be attributed to the tocotrienol content of palm vitamin E. Therefore, tocotrienols play an important role in bone calcification.
Asia Pac J Clin Nutr 2002
PMID:Tocotrienols are needed for normal bone calcification in growing female rats. 1223 Feb 32

Vitamin E was discovered over 75 years ago, yet it has been only recently recognized that human vitamin E deficiency occurs as a result of fat malabsorption syndromes, defects in lipoprotein metabolism, and defects in the gene for the *-tocopherol transfer protein. Although the frequency of human vitamin E deficiency is unknown, it is likely that it is very rare. In individuals at risk, it is clear that vitamin E supplements should be recommended to prevent deficiency symptoms. What about their use in normal individuals? Vitamin E supplementation in normal individuals is quite controversial. It has been assumed that usual dietary vitamin E intakes are adequate because human vitamin E deficiency is rare and experimental vitamin E deficiency difficult to produce in laboratory animals. A continuing problem in nutrition is whether nutrients have beneficial effects when consumed in amounts in excess of those 'required' by the body. For most vitamins, excess amounts are wasted and provide no added benefits. Indeed, some fat soluble vitamins can be stored and excess amounts become toxic. Antioxidant nutrients may, however, be different. Heart disease and stroke, cancer, chronic inflammation, impaired immune function, Alzheimer's disease: a case can be made for the role of oxygen-free radicals in the etiology of all of these disorders and even in aging itself. Do antioxidant nutrients counteract the effects of free radicals and thereby ameliorate these disorders? And if so, do large antioxidant supplements have beneficial effects beyond 'required' amounts or even in amounts beyond those that could be obtained from a well-balanced diet? These are questions for which not only scientists, but also the public, are eagerly awaiting the answers.
Asia Pac J Clin Nutr 1998 Dec
PMID:Recent advances of vitamin E pathophysiology. 2439 81

Vitamin E has been of interest to sports people for many years, with reports of its dietary supplementation in the 1950s. In the last decade there has been a resurgence in the interest in the relationship between vitamin E and athletic performance and animal studies have demonstrated that endurance is reduced in vitamin E deficiency. Much of the recent research has centred around the antioxidant properties of vitamin E and it seems that these properties are in part responsible for the improvement of aerobic power of humans at medium to high altitude venues following supplementation of the vitamin. However, there have been no similar reports relating to sea-level performance. On the other hand, one recent study has indicated that supplementation of vitamin E to athletes consuming the recommended daily intake (RDI) elicited a reduction in indicators of muscle damage following an exercise bout. Furthermore, vitamin E is implicated in maintenance of both optimal immune function and optimal blood viscosity, both factors being important in athletes' ability to train and compete, but it remains to be seen whether supplementation over the RDI has any beneficial effects. So, there seems 'little doubt that vitamin E deficiency will impair athletic performance and there is also some evidence that supplementation of vitamin E on top of the RDI may provide some advantage for the intensely training athlete, especially those training at altitude.
Asia Pac J Clin Nutr 1993 Nov
PMID:Vitamin E and athletic performance. 2439 81

Cataract (opacity of the lens) and age-related degeneration of the macula of the retina are very common causes of disability in old age, and people are living longer. It seems likely that both of these conditions result from gradual photo-oxidative damage. The proteins in cataractous lenses are oxidized and 50 per cent of the fatty acids in membranes of retinal photo-receptors are highly polyunsaturated. The eye normally has unusually high concentrations of vitamin C and zinc which could have protective functions against free radical damage. For cataracts five reported case-control studies are reviewed and two prospective studies one of which included a very large number of subjects. Vitamin intakes were estimated from dietary histories or blood levels. In five of the six studies in which vitamin C was measured it appeared to be protective and vitamin E and carotenoids appeared protective in 5/7 studies. Other descriptive epidemiological studies are going on, including one in the Blue Mountains near Sydney. It is concluded that controlled trials of antioxidant nutrients for cataract prevention are now warranted. As to age-related muscular degeneration (ARMD), severe vitamin E deficiency is known to cause (a different type of) retinal degeneration spontaneously in humans (with cystic fibrosis or abetalipoproteinaemia) and experimentally in animals. Only three human case-control studies of ARMD and diet have been reported thus far and no clear relationship with any particular nutrient has emerged yet. Supplements containing antioxidant vitamins and zinc are being advertised and used in the USA and elsewhere but this is ahead of the evidence. More observational studies are needed and the US National Eye Institute is planning a 10 year intervention study, known as AREDS (Age-Related Eye Disease Study).
Asia Pac J Clin Nutr 1993 Nov
PMID:Nutrients and degenerative eye diseases. 2439 83