New studies highlight risks of vitamin supplements

by Jean-Louis Santini

New research is prompting a fresh look at the value of vitamin supplements, with some surprising results indicating that taking too many supplements of some could be harmful.

The research is forcing scientists to rethink the use of supplements with , which had been seen as beneficial in preventing cancer, and other .

"Everybody is confused," admitted Toren Finkel, head of the Center for at the National Institutes of Health (NIH).

While logic would seem to dictate that taking vitamins and antioxidants should help fight illness and disease, Finkel said in an interview that the clinical data "are pretty consistently showing no benefit."

"So that means we have to go back and think about some of the assumptions we have made along the way in terms of what the mechanism for these diseases are and how things like oxidants play a role in those diseases," he told AFP.

Finkel explained that while it has long been believed that oxidants -- produced by the body or introduced through external sources such as pollution -- were unhealthy, the research paints a more complex picture.

"You have to go back to the lab and try to design experiments you can do a little simpler with cells or animals... to better understand the role of oxidants and vitamins," he said.

"For years, we were using these supplements without knowing the effects on the body."

A study published on October 11 in the indicates a 17 percent increase in the risk of developing among men who take high doses of vitamin E.

Another recent US study conducted among women and published on October 10 revealed that multivitamins -- commonly taken in the United States -- were useless and actually gradually contributed to a higher risk of .

As far back as 2007, researchers had established a link between taking and an increased risk of adult diabetes.

For David Schardt, a nutritionist at the non-profit Center for Science in the Public Interest, the problem is that "people think more is better and that (supplements) are harmless."

"We are finding out that some of these vitamins taken alone in large amounts may have effects we did not predict, we did not understand and we did not anticipate," Schardt said.

He added that the country has "a lot of people who believe, almost like a religion, in their vitamins" -- a faith encouraged by an industry that generates $20 billion a year in the United States, where more than half of the population takes some kind of vitamin supplement.

Moreover, US manufacturers are "free to say almost anything they want" about the virtues of supplements, Schardt explained, adding: "The only thing the Food and Drug Administration does not let them make are claims about disease."

Patsy Brannon, a Cornell University professor who served on an NIH panel on multivitamins, mineral supplements and chronic diseases, said that those who take supplements are often those already getting nutrients from their food.

"So the people who are choosing supplements are maybe the people who don't need them," she said. "So they are not thinking about their total intake and that I think is a concern."

Experts agree that multivitamins and other are useful for certain groups such as pregnant women and elderly people suffering from vitamin deficiencies.

But for the general population, a healthy balanced diet rich in fruits, vegetables and fiber as well as animal-based protein will provide the proper vitamins and nutrients needed, Brannon said.

A study published in late August in the Journal of Nutrition showed that a significant number of Americans did not eat well and did not take .

Twenty-five percent of respondents had a vitamin C deficiency, 34 percent were not getting enough vitamin A and 60 percent needed more . All three are found in fruits and vegetables.

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dutchman
not rated yet Oct 17, 2011
There have alwys been "food supplement" deniers, despite actual clinical studies at various universities (like the recent findings about the benefits of vitamin D.)

"But for the general population, a healthy balanced diet rich in fruits, vegetables and fiber as well as animal-based protein will provide the proper vitamins and nutrients needed, Brannon said."

Mr Brannon, good luck with that! Most of us don't have the time to prepare proper meals. Uncooked food can carry food-born illness - some deadly. Heat (as in cooking) destroys vitamin C - as does exposure to oxygen (as in air). So now what?

What part of big pharma has been funding your research?

Oh, and BTW: FRUIT is both singular AND PLURAL. Fruits is redundant, like sheeps.
Nerdyguy
1 / 5 (3) Oct 17, 2011
"What part of big pharma has been funding your research?"
...dutchman

Where is the logic in suggesting "big pharma" is backing Dr. (not Mr.) Brannon's research? According to the article, her only recommendation is a re-think on the AMOUNT of vitamins ingested by an individual. This conclusion has been reached by a number of similar studies over the last few years. But, nowhere is Brannon or the general research mentioned here recommending a switch to a pharmaceutical product of any kind. Personally, I use a variety of vitamins/supplements. Does this make me a "food supplement believer"?

DrNutrients
1 / 5 (3) Oct 17, 2011
Why not cover real news worth articles showing how the FDA allowed oil tainted seafood to be sold in US markets and abroad? This study was published this week in the journal Environmental Health Perspectives (impact factor of 6).
DrNutrients
2.4 / 5 (5) Oct 17, 2011
As a well-published neuroscientist in a major University conducting research on the benefits of nutrients and flavonoids for neurodegenerative disease, I find news coverage of this flawed study incompetent and the journal which published it irresponsible in its actions. How many of these flawed anti-vitamin studies have to be published and then exaggerated by MSM before real scientists with integrity stand up against this? A scientific rebuttal of this anti-vitamin study was published online by the Life Extension Foundation entitled Findings from Flawed Study Used to Discredit Multivitamin/Mineral Supplements. Google it, since I am not allowed to post URLs.
godistruth
2 / 5 (4) Oct 22, 2011
The real threat to human health is from genetically engineered food, pesticides, unhealthy contaminated water, processed unnatural foods and artificial additives..NOT too many vitamins. With regards to vitamin and mineral supplements brand QUALITY is crucial, ALL of the negative 'tests' i have read used substandard low quality supplements.