Vitamin E: A Rebuttal to the claim that high intake is harmful

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Vitamin E: A Rebuttal to the claim that high intake is harmful

http://www.willner.com/article.aspx?artid=29

 

CRN Questions Conclusions Reached by Researchers in Recent Vitamin E

Meta-Analysis

11/10/2004 - Council for Responsible Nutrition (CRN)

 

Washington, D.C., November 10, 2004 – A meta-analysis on vitamin E

and all-cause mortality (ACM) from today's on-line issue of Annals

of Internal Medicine inappropriately tries to draw conclusions for

the whole population based on a combination of studies of people who

were already at grave risk with existing diseases including cancer,

heart disease, Alzheimer's, Parkinson's and kidney failure, says the

Council for Responsible Nutrition (CRN).

 

The researchers themselves noted limitations in their meta-analysis,

stating " the generalizability of the findings to healthy adults is

uncertain. Precise estimation of the threshold at which risk

increases is difficult. " Yet they go on to make sweeping

generalizations about the use of vitamin E and all-cause mortality

for the whole population, although they provide no evidence that

these kinds of effects would occur in healthy populations.

 

" This is an unfortunate misdirection of science in an attempt to

make something out of nothing for the sake of headlines, " comments

John Hathcock, Ph.D., vice president, scientific and international

affairs, CRN.

 

The meta-analysis combined 19 individual studies, eighteen of which

showed no statistically significant increase in mortality, squeezing

out an overall finding of risk. Combining numerous clinical trials

into a single large cohort gave greater statistical power but failed

to capture the limitations of each study included.

 

Most of the trials involved middle-aged to elderly persons who had

heart disease or other serious conditions or were at risk of

disease. The placebo groups had an ACM rate of 1022/10,000 and the

high-dose (defined by the researchers as 400 IU and up) vitamin E

subjects had an ACM increase of 39/10,000.

 

Says Dr. Hathcock, " The overall conclusion of this meta-analysis is

driven by the results from a few of these clinical trials, some of

which are suspect and/or dated. For example, the WAVE trial (Waters

et al., 2002) made no correction for multiple comparisons, and found

one of 22 comparisons `significant.' This is 1/22 whereas 1/20 would

have been expected on a random basis. In other words, they found

nothing. "

 

Dr. Hathcock added, " In reviewing the totality of evidence on

vitamin E, including all clinical trial data and several large

observational studies, CRN agrees with the Institute of Medicine in

finding vitamin E supplements safe at levels of at least up to 1,000

mg (1,600 IU) for normal, healthy adults. This meta-analysis

provides no convincing evidence to the contrary. "

 

The Council for Responsible Nutrition (CRN), founded in 1973, is a

Washington, D.C.-based trade association representing dietary

supplement industry ingredient suppliers and manufacturers. CRN

members adhere to a strong code of ethics, comply with dosage limits

and manufacture dietary supplements to high quality standards under

good manufacturing practices. For more information on CRN, visit

http://www.crnusa.org.

 

 

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Carotech Communication Regarding Johns Hopkins vitamin E Meta-

analysis

 

11/12/2004 - Carotech, Inc.

 

TO " E " OR NOT TO " E " ?

 

This Technical Communication is in response to an article published

on Nov 10th 2004 in the Annals of Internal Medicine. Researchers at

Johns Hopkins examined 19 different vitamin E studies between 1966

and 2004 to a meta-analysis. 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.

 

 

Meta-analyses are often highly speculative because of the different

variables in each of the studies such as source of vitamin E

(natural or synthetic), study duration, health/disease condition of

subjects, etc. Hence, they by no means offer definitive proof of

anything, due to the lack of uniform protocols and patient groups

 

 

Perhaps - on the other hand, 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. As a matter

of fact, we have seen this before - in 1996 with the beta-carotene

debacle (The ATBC and CARET studies). These two studies provide

evidence that taking beta-carotene alone rather than a multi-

carotenoids (beta-carotene, alpha-carotene, gamma-carotene,

lycopene, lutein - as produced 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.

 

 

Similarly, a high dosage of alpha-tocopherol alone has been shown to

deplete the body's gamma-tocopherol. Despite alpha tocopherol's

action as an antioxidant, gamma tocopherol is required to

effectively remove the harmful peroxynitrite-derived nitrating

species. 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.

 

 

Taking a single form of vitamin E (ie : alpha-tocopherol alone)

denies the very fact that nature put seven (7) different forms of

tocopherols and tocotrienols there for a reason.

 

 

We should be taking the wholesome full spectrum vitamin E : d mixed

tocopherols + d-mixed tocotrienols (E COMPLETE) - as that which is

produced and found in nature. Like the carotenoids, all these

different forms of vitamin E work synergistically and depends on

each other for optimum functionality.

 

 

Natural phytonutrients just don't work well in isolation from each

other. We 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 that this would be safer than just the alpha-

tocopherol alone.

 

Carotech Inc - The Leading & Largest Supplier of Full Spectrum

Tocotrienol Complex

 

 

 

 

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Canadian Health Food Association reminding Canadians of

scientifically-proven benefits of regular vitamin E consumption

 

11/12/2004 - Canadian Health Food Association

 

TORONTO, Nov. 11 /CNW/ - The Canadian Health Food Association (CHFA)

is joining the US-based Council of Responsible Nutrition (CRN) and

Australia's Complementary Healthcare Council in reminding people

about the body of research proving the many health benefits of

regular vitamin E consumption. The CHFA is also cautioning Canadians

about changing their vitamin E consumption habits based on recent

attention being paid to a study that raises questions about vitamin

E, because the study has limited relevance for healthy Canadians.

 

" There is a plethora of international research that supports the

benefits of regular vitamin E consumption and we want to reassure

Canadians who regularly take vitamin E that the recent study

published in the Annals of Internal Medicine is not a cause for

concern because of the age and health of the people involved in the

study, and the type of vitamin E (natural or synthetic) on which its

results are based, " says Valerie Bell, President, Canadian Health

Food Association.

 

 

" While we support ongoing research in the field, we are concerned

that Canadians are being mislead in terms of what they've heard or

read recently about vitamin E. It's important that they understand

that the study referred to in these reports drew its conclusions on

a combination of studies involving people who were already at grave

risk with existing diseases including cancer, heart disease,

Alzheimer's, Parkinson's and kidney failure. The researchers

 

themselves acknowledge that the results are generalizations and the

relevance of the findings to the general population is uncertain.

Secondly, the combination of trials on which the results are based

may not have used the

 

same form of Vitamin E, or necessarily the form of Vitamin E that

the majority of people generally use. "

 

To E or not to E

 

Bell says that a number of Canadian experts support the CHFA

position and are also reminding Canadians of the many scientifically-

proven health benefits of regular vitamin E consumption - including

the prevention and treatment of

 

cardiovascular disease - that a large body of research clearly

supports.

 

 

" We encourage Canadians to talk to their natural health provider or

doctor before making any change in their vitamin E consumption

habits, " saysBell.

 

About the Canadian Health Food Association

 

The Canadian Health Food Association (CHFA) is a non-profit

federally chartered trade association. Its 1,300 members include

retailers, manufacturers, wholesalers, distributors, consultants and

other member associations that are involved in a variety of industry

sub sectors such as supplements, vitamins, herbals, homeopathics,

sports nutrition products, natural foods and organic products. CHFA

members believe that access to natural health foods and nutritional

supplements is the democratic right of every Canadian. To that end,

they are committed to protecting and furthering the interests of the

Canadian natural products industry.