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Vitamin E linked to 9,000/million User Deaths

British Study Finds Vitamin Supplements May Increase Cancer Risk
From Consumer Affairs.com


Oct 01 '04

Not only do vitamin supplements not protect against gastro-intestinal cancer, they may slightly increase the risk of cancer, according to a systematic review and meta-analysis of previously published randomised trials in this week’s issue of THE LANCET, a leading British medical journal.

If the findings are correct, 9,000 in every million users of such vitamin supplements will die prematurely as a result of taking something they think is good for them. Miller said his team pulled together results from 19 studies representing almost 136,000 people and found that those taking high doses of vitamin E (400 international units or greater) had a 5 percent greater risk of dying over four years than those who were taking either less than 150 IU or a placebo.

"The prospect that vitamin pills may not only do no good but also kill their consumers is a scary speculation given the vast quantities that are used in certain communities,” David Forman of the University of Leeds and Douglas Altman, Cancer Research UK, said in an accompanying commentary.

The researchers cautioned that the findings are preliminary and "(do) not offer convincing proof of hazard," pending further studies.

The mortality analysis in Bjelakovic and colleagues’ review is work in progress, and does not offer convincing proof of hazard. In the event that a hazard is established from a complete review, these researchers will need to identify which specific interventions are associated with any risk. It is unlikely that all supplements will exert a similar effect and it will be vital to establish the safety profile for those with demonstrated benefits.”

"The human diet is a complex mix of oxidants and antioxidants. Excess oxidants can cause cancer by inducing gene mutations," said Goran Bjelakovic, a professor at several European university, the study's lead investigator.

The investigators identified 14 randomised trials totalling over 170,000 participants. Overall, the results did not show any protective effect of supplementation with beta-carotene, vitamins A, C, E, and selenium (alone or in combination) compared with placebo on oesophageal, gastric, colorectal, pancreatic, and liver cancer incidences.

In half the trials, there was a small but statistically significant increase in mortality among people taking antioxidants compared with placebos. The results also showed that two combinations of supplements were associated with increased mortality risk: beta-carotene and vitamin A, and the combination of beta-carotene and vitamin E.

Four of the trials suggested that selenium was associated with a reduction in gastro-intestinal cancer risk.

“We could not find evidence that antioxidant supplements can prevent gastrointestinal cancers; on the contrary, they seem to increase overall mortality. The potential preventive effect of selenium should be studied in adequate randomised trials," Dr. Bjelakovic said.

Previous studies have failed to demonstrate that antioxidant vitamin supplements reduced the risk of heart disease among people at high risk of vascular disease.



Copyright 2003-2004 ConsumerAffairs.com Inc. All Rights Reserved.

Another risk that of heart attacks

 

Another bit of the naturalistic, good for the body, claims bites the dust—at least for people who demand evidence.  One claim is that Vitamin E is healing, and thus promotes recover from heart attacks.  Thirty-five years ago I heard on the radio a medical doctor--who was into the naturalistic lore—that his patients were having exceptionally rapid recoveries from heart attacks because of vitamin E.  Sounded convincing, except for its source and that if this was the case, the medical establishment would have within a few years been giving vitamin E to accelerate recovery from heart attacks.  A second claim was that vitamin E reduces the risk of cancer.  Now a study shows.  Recently published large population studies show that it has a slight effect to the contrary, raises the risk.  --jk

 

 

Health Day, March 05

 

Vitamin E Ups Heart Failure Risk
Study also finds supplement doesn't prevent cancer or heart disease


by Serena Gordon, HealthDay Reporter | Mar 15 '05


Vitamin E doesn't help prevent cancer or cardiovascular disease and can, in fact, increase the risk of heart failure.  That's the conclusion of an extended trial of thousands of older people with a history of cardiovascular disease or diabetes who were randomly assigned to take either 400 I.U. of vitamin E or a placebo.

The results, published in the March 16 issue of the Journal of the American Medical Association, found there was up to a 19 percent increase in the risk of heart failure in the study volunteers who took vitamin E compared to those on the placebo.

"I don't think people have to panic" if they've been taking vitamin E, said study author Dr. Eva Lonn, a professor of medicine at the Population Health Research Institute at McMaster University in Hamilton, Ontario, Canada.

She noted that the incidence of heart failure was lower in study participants than the incidence of either heart attack or stroke. And it's also possible the findings were simply due to chance, because so far other studies haven't shown this side effect, Lonn said. Still, she added, most other studies haven't looked specifically for heart failure, either.

In younger, healthier people, Lonn said, vitamin E is probably safe, "but I think it would be a waste of time." She said numerous studies, including hers, have found no protective effect from vitamin E against heart disease or cancer.

At least one expert from the dietary supplement industry disagrees with Lonn, however.

"This study is not the final word," said Annette Dickinson, president of the Council for Responsible Nutrition, a trade association representing the dietary supplement industry. "This was a study done on older people with serious preexisting disease, taking a number of medications, and their findings have not been confirmed in other studies."

"I think that healthy people can still be confident in vitamin E," Dickinson added. "A number of studies have shown benefits in some types of cancers, eye diseases, and neurological conditions, such as Alzheimer's."

The new study is a continuation of the Heart Outcomes Prevention Evaluation (HOPE) trial, which included data on 9,541 people who were over 55 and either had a history of heart disease or diabetes. The original study was conducted from December 1993 through April 1999. Results of that study were published in the New England Journal of Medicine in 2000. Study volunteers were randomly chosen to receive either 400 I.U. daily of vitamin E or a placebo.

Lonn said many researchers felt the original trial was conducted for too short a period of time. It was suggested that if vitamin E were going to show a benefit, it would likely come from long-term use.

The Ongoing Outcomes (HOPE-TOO). Almost 4,000 people from the original study consented to continuing in the extended study. The researchers were also able to obtain follow-up information through medical records for many people who didn't stay in the study.

HOPE-TOO found no evidence that vitamin E protects against cancer or cardiovascular disease. In fact, the researchers found that the rate of heart failure increased in people taking vitamin E.

Lonn said the overall increase in heart failure risk was 13 percent. For heart failure requiring hospitalization, the risk was increased by 19 percent in the vitamin E group, she said.

While Lonn said the mechanism that might cause vitamin E to increase the risk of heart failure isn't clear, it may be that in the presence of oxidative stress, vitamin E may act as a pro-oxidant, rather than an antioxidant.

But, again, Lonn said she doesn't think anyone who's been taking vitamin E needs to worry. Her biggest concern, she said, is that many people who take vitamins and other dietary supplements may think they don't need to take other steps to prevent cancer and heart disease, such as getting enough exercise and eating right.

Dickinson said, "There needs to be more evaluation of these findings. I agree that it's a good idea to examine those results, but I think it's not likely to show it's a chance finding."

More information

To learn more about vitamin E, visit the National Institutes of Health's Office of Dietary Supplements.


SOURCES: Eva Lonn, M.D., staff cardiologist, Hamilton Health Sciences Corporation, and professor of medicine, Population Health Research Instutite at McMaster University, Hamilton, Ontario, Canada; Annette Dickinson, Ph.D., president, Council for Responsible Nutrition, Washington D.C.; March 16, 2005, Journal of the American Medical Association


Copyright 2004-2005 ScoutNews, LLC. All rights reserved.

 

 

Wipe the other cheek

 

From Health Day Jan 05

 

The conference followed the release of a John Hopkins study in November that found elderly, ill patients who took vitamin E daily at doses of 400 International Units (IUs) or more suffered a 6 percent increase in mortality compared to those who took placebos.

 

 

 

MORE CONFIRMATION OF VITIMAN E RISK

 

People Not Heeding Vitamin E Warnings
Many taking high daily doses despite evidence it may be harmful

 

by Alan Mozes, HealthDay Reporter | Jul 19 '05

 

Many Americans still take high daily doses of vitamin E despite mounting evidence that the vitamin offers no health benefit and could be dangerous, a new study finds.  The researchers found that just over 11 percent of American adults routinely consume at least 400 IUs of vitamin E on a daily basis. Another 26 percent of American adults take supplements that include lower amounts of the vitamin.  Reporting in the July 19 issue of Annals of Internal Medicine, the authors referred to a range of recent studies that suggested vitamin E supplementation in doses at or exceeding 400 IUs may increase the risk for premature death from chronic illness such as heart disease and cancer.  "Basically, what we're trying to do is let folks know that many Americans are still consuming too much vitamin E, and that too much is really not that good," said study co-author Ali H. Mokdad, of the Chronic Disease Center at the Centers for Disease Control and Prevention in Atlanta.

Vitamin E supplements in the 400 IU range far exceed the current federally recommended dietary allowance (RDA) guideline set to reflect the daily nutritional needs of most healthy men, women and children. The RDA for vitamin E --according to the National Institutes of Health (NIH)-- is 22.5 IUs for adults.  The NIH points out that vitamin E deficiency is rare, noting that the nutrient is found naturally in many food sources such as plant oils (including vegetable oil and margarine), leafy green vegetables, whole grain cereals, liver, egg yolks, milk, nuts, seeds and butter.  Mokdad and his colleagues analyzed vitamin E supplementation data among more than 4,600 white, black and Mexican-American adult men and women who had been included in the 1999-2000 National Health and Nutrition Examination Survey.

All the participants had completed interviews and questionnaires on their daily dietary intake, and all underwent blood tests and neurological, fitness and oral health evaluations.  White adults were also generally more likely to take vitamin E supplements, as were those patients with a history of heart disease, stroke or diabetes.  Those who regularly took vitamin E supplements were also more likely to ingest supplements that included vitamin C and beta-carotene. The researchers suggested that this combination of supplements further added to the potential harmful effects related to the ingesting of high doses of vitamin E.  The authors concluded that high-dosage vitamin E supplementation is common, and that concerns about the practice should be raised by health-care professionals who could advise their patients of potential health risks.

complicating efforts to promote accurate public health information about vitamin E.

Both Mokdad and his colleague, Dr. Umed A. Ajani, said that the exact mechanism by which high-dose vitamin E supplementation poses health risks is not yet fully understood. However, they emphasized, the danger is real.  "We know there is an increased risk, and at this point this affects a sizeable proportion of the U.S. population," Ajani said.  "There was this theory that antioxidants such as vitamin E will lead to less blockage in the arteries," said Mokdad. "But there have been several clinical trials since that show that, in reality, this is not true. Unfortunately there was a lot of media attention given to the antioxidant theory, and it seems people haven't kept up with the most recent data that showed, in fact, that it may harm you a little bit."   

Both Mokdad and Ajani agreed that vitamin supplementation overall is ripe for abuse and poorly understood.  "There may be some supplements out there that are good for people to take now and then," Ajani added. "But in the case of vitamin E, the research does not support any benefit, and in fact it may harm you."

Dr. Jay Brooks, chief of hematology/oncology at the Ochsner Clinic Foundation in New Orleans, concurred.  "Everyone thinks that taking vitamins and supplements is perfectly OK to do," Brooks said. "But these are active drugs, and we don't understand completely what they do. So, I do not recommend to any of my patients to be taking extra dosage of vitamins, unless they're involved in a research study."  "I know of no disease . . . that can be prevented or treated by taking vitamin E," Brooks added. "So, I don't take it personally to prevent prostate cancer or other diseases. We just don't know if it works, and it may actually be detrimental."

More information

For more on vitamin E, check out the National Institutes of Health's Office of Dietary Supplements.

SOURCES: Ali H. Mokdad, Ph.D., and Umed A. Ajani, M.D., Chronic Disease Center, CDC, Atlanta; Jay Brooks, M.D., chief, hemotology/oncology, Ochsner Clinic Foundation, New Orleans; July 19, 2005, Annals of Internal Medicine