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Old November 11th, 2004, 22:04
sysadmin sysadmin is offline
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Vitamin E Supplementation of 150 IU a day or Greater May Be Hazardous



[Annals of Internal Medicine] This study was a retrospective review (meta-analysis) of the literature on supplementation with vitamin E. The researchers conclude that supplementation of vitamin E at levels greater than or equal to 150 IU a day is likely to be hazardous. COMMENT: supplementation with a balanced multivitamin/mineral supplement still appears to be reasonable, but a separate vitamin E supplement (which usually contains a megadose level of vitamin E) possibly is harmful to most people.

http://www.annals.org/cgi/content/a...0501040-00110v1
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Old December 12th, 2004, 11:18
carot3 carot3 is offline
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Re: Vitamin E Supplementation of 150 IU a day or Greater May Be Hazardous

Not All Vitamin E Should Be Condemned : A Different Perspective
By, WH LEONG, Vice President; Carotech Inc (carot3@aol.com)

A meta-analysis of 19 human studies with vitamin E was published recently in the November 2004 issue of the Annals of Internal Medicine. Researchers at Johns Hopkins examined 19 different vitamin E studies between 1966 and 2004. The total number of subjects (age 47 - 84 years old) in these 19 studies was 135,967. The dosages of vitamin E ranged from 16.5 to 2000 IU per day. The meta-analysis suggests that too much of vitamin E (400IU or more per day) increases the risk of all-cause mortality.

In light of this controversial vitamin E meta-analysis publication and the so many response by experts to it in the media, perhaps, one should look at vitamin E supplementation from a different perspective - that vitamin E should be taken as a wholesome mixture of d-mixed tocopherols and d-mixed tocotrienols. Taking a single form of vitamin E (ie : alpha-tocopherol alone) denies the very fact that nature put seven (7) other forms on vitamin E (ie : gamma-tocopherol, beta-tocopherol, delta-tocopherol, alpha-tocotrienol, beta-tocotrienol, gamma-tocotrienol and delta-tocotrienol) out there for a reason.

As a matter of fact, we have seen this before - in 1996 with the beta-carotene debacle (The ATBC and CARET studies)1,2. These two studies provide evidence that taking beta-carotene alone rather than a multi-carotenoids (beta-carotene, alpha-carotene, gamma-carotene, lycopene, lutein - as produce in nature), may increase the cancer risks among smokers. This may be because all these carotenoids work synergistically as a team - recharging and supporting each other to confer the health benefits.

It goes to show that a single nutrient vitamin E (ie : alpha-tocopherol - synthetic or natural) is not the panacea. It is against conventional wisdom to take mega-doses of one nutrient without considering the potential side effects.

Similarly, high dosage of alpha-tocopherol alone has been shown to deplete the body's gamma-tocopherol3. Despite alpha tocopherol's action as an antioxidant, gamma tocopherol is required to effectively remove the harmful peroxynitrite-derived nitrating species4. Because large doses of dietary alpha tocopherol displace gamma tocopherol in plasma and other tissues, the current wisdom of vitamin E supplementation with primarily alpha tocopherol should be reconsidered. Other forms of vitamin E - gamma-tocopherol, delta-tocopherol and certainly tocotrienols have been proven to have unique health properties as well.

Tocotrienols on the other hand have been proven to be beneficial to the cardiovascular system. It is a potent antioxidant (40-60 times more potent) and has been proven to lower total blood cholesterol as well as reverse arterial blockage in Carotid Stenosis patients 5,6,7,8,9,10. In a recent NIH-funded study in collaboration with Ohio States University Medical Center and Carotech Inc (Tocomin®), it was found that tocotrienols especially alpha-tocotrienol are much more potent than tocopherol in protecting the neurons from glutamate-induced neuro-degeneration 11,12,13.

In many foods, alpha- and gamma-tocopherol account for most of the vitamin E activity. While tocopherols are generally present in common vegetable oils (i.e. soy, canola, wheat germ, sunflower), tocotrienols, on the other hand, are concentrated in cereal grains (i.e. oat, barley, and rye, rice bran), with the highest level found in crude palm oil. It is unfortunate that not many consumers are aware of tocotrienols due to the low level in the Western diets 14.

Looking at the whole realm of vitamin E research, it is prudent to take the wholesome full spectrum vitamin E : d mixed tocopherols + d-mixed tocotrienols - as what is produce and found in nature. Mimicking nature is the best way for supplementation. Like the carotenoids, all these different forms of vitamin E work synergistically and depend on each other for optimum functionality.

Natural phytonutrients just don't work well in isolation from each other. I sincerely believe (from scientific evidence) that most people would benefit from taking a full spectrum Vitamin E supplement that consists of d-mixed tocopherols + d-mixed tocotrienols. And it would be safer than just the alpha-tocopherol alone.

Resource Information for Vitamin E

CRN’s Resource Website for Vitamin E : http://www.crnusa.org/vitaminEissafe.html

Tocotrienol Educational Website : www.tocotrienol.org

Scientific References :-

1. Albanes D, et al., “The effect of vitamin E and beta-carotene on the incidence of lung cancer and other cancers in male smokers”, The New England Journal of Medicine, 1994; 330 : 1029-1035.
2. Heinonen, OP, et al., “The effect of Vitamin E and beta carotene on the incidence of lung cancer and other cancers in male smokers – The Alpha-Tocopherol and Beta Carotene Cancer Prevention Study”, The New England Journal of Medicine., 1994; 330 (15): 1029 - 1035
3. Handelman et al, “Oral alpha-tocopherol supplements decrease plasma gamma-tocopherol levels in human”, Journal of Nutrition, 1985; 115(6) : 807-813.
4. Cooney RV, Franke AA, Harwood PJ, Hatch-Pigott V, Custer LJ, Mordan LJ., “g-Tocopherol detoxification of nitrogen peroxide: Superiority to a-tocopherol”, Proc Natl Acad Sci USA. 1993; 90: 1771-1775.
5. Tomeo AC, Geller M, Watkins TR, Gapor A, and Bierenbaum ML. “Antioxidant effects of tocotrienols in patients with hyperlipidemia and carotid stenosis”. Lipids 1995; 30: 1179-1183.
6. Bierenbaum ML, et al., “Palm oil antioxidant effects in patients with lyperlipidaemia and carotid stenosis – 2 year experience”, Asia Pacific J. of Clinical Nutrition 1997; 6(1):72-75.
7. Serbinova E, Khwaja S, Catudioc J, et al. “Palm oil vitamin E protects against ischemia/reperfusion injury in the isolated perfused Langendorff heart”. Nutr Res 1992; 12: S203-S215.
8. Qureshi AA, Bradlow BA, Brace L, et al., “Response of hypercholesterolemic subjects to administration of tocotrienols”. Lipids 1995; 30: 1171-1177.
9. Khor HT, et al., “Effect of a palm oil vitamin E concentrate on the serum and lipoprotein lipids in humans”, American Journal of Clinical Nutrition, 1991; 53 : 1027S – 1030S.
10. Sen CK, Khanna S, Roy S, Packer L., “Molecular basis of vitamin E action: Tocotrienol potently inhibits glutamate-induced pp60c-Src kinase activation and death of HT4 neuronal cells”, J Biol Chem 2000; 275 : 13049-13055.
11. Sen CK, et al., “Molecular Basis of Vitamin E Action - Tocotrienol modulates 12-lipoxygenase, a key mediator of glutamate-induced neurodegeneration”, J. Biol. Chem., 2003; 278 (447) : pp : 43508 43515.
12. Sen, Chandan, et al., “Vitamin E sensitive genes in the developing rat fetal brain : a high density oligonucleotide microarray analysis”, FEBS Letter, 2002; 530 : pp : 17-23
13. Dial S, Eitenmiller RR, “Tocopherols and tocotrienols in key foods in the US diet”, In : Nutrition, Lipids, Health and Disease, Ed : Ong ASH, Niki E, Packer L, AOCS Press, Champaign IL, 1996.
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