Get Your Vitamins From Food, Not Pills

[Guest guest]

One in three women and one in four men in the United States take

vitamin pills. If you are among them, you may be doing more harm than

good. In a wake up call to the multibillion dollar vitamin pill

industry, a review of 67 randomized trials of vitamin pill effects on

life and health has found that taking vitamin pills may shorten life

(Cochrane Database of Systematic Reviews, Issue 1, 2008). Other

studies have shown that taking vitamin pills may increase risk for

cancers and heart attacks.

This review of 232,000 adults showed that those taking beta-carotene,

vitamin A, C, and E and selenium gained no benefit over those who

took placebos or no pills. " The findings show that, if anything,

people in trial groups given beta-carotene, vitamin A and vitamin E

showed increased rates of mortality. There was no indication that

vitamin C and selenium may have positive or negative effects. "

The study was originally set up to see if antioxidant vitamin pills

and minerals prevent gastrointestinal cancers. It found no protection

whatever. Instead, an increased death rate of 16 percent was seen in

those taking vitamin A pills, seven percent with beta- carotene, and

seven percent with vitamin E. No increased death rate was seen in

those taking vitamin C or selenium.

Dear Dr. Mirkin: Would you please explain how vitamin pills could

affect lifespan, as you reported in last week's issue?

The issue of vitamin supplements is far from settled.

Most doctors take multivitamins themselves and recommend them to

their patients. However, I continue to believe that it is better

to get vitamins in whole foods than in pills.

Most vitamins are parts of enzymes that start chemical

reactions in your body. Each chemical reaction produces end products

that are changed by further chemical reactions from other vitamins to

other products that benefit your body. When you take a vitamin that

has been isolated from the hundreds of other substances found in

foods, that enzyme causes a chemical reaction that accumulates a

disproportionate amount of its end products. If the substance that

acts as an enzyme for the next chain of chemical reactions is not

available, you can accumulate end products that may be harmful.

For example, people who take niacin to lower cholesterol show

a marked elevation of homocysteine, a major risk factor for heart

attacks. Homocysteine levels are raised by a deficiency of B12,

folic acid and pyridoxine. When you eat your niacin in whole grains,

all of those components are present, along with many others whose

functions we may not yet understand.

Several of you asked for a link to the study I mentioned last

week; it has been added to the issue at

http://www.mrw.interscience.wiley.com/cochrane/clsysrev/articles/CD007

176/frame.html

[Guest guest]

Hi Dr. Blair:

Thank you for that post. Do you have an opinion, or do you know of studies that can help determine, whether it is inadvisable to take supplements of nutrients one knows one's diet to be deficient in - compared with the RDAs?

I understand it is better to get the required nutrients from food where practicable. But my impression is that the vast majority of people, even those who believe they are eating a healthy diet - especially, of course, those eating a notably-low-calorie healthy diet - almost always get less than the RDAs of zinc and vitamins E and D, and sometimes selenium also. And often other nutrients too of course, depending on what it is they generally eat.

So, in your view, if that is the situation, is it better to go with less than the RDA? Or better to supplement just up to the RDA, but not too far beyond? (400 IU of vitamin E just once a week will put anyone way over the RDA, for example. So taking it daily could certainly be described as 'overdosing'. I take one small folic acid pill weekly and my serum folate is three times the low end of the reference range.)

And to push the argument a little further: should essential nutrients of all kinds, even when obtained from foods, be limited to levels not too far in excess of the RDA? There is a sort of mantra in CRON circles to maximize essential nutrients on the lowest practicable caloric intake. Might maximization represent overdosing, even when obtained from food? Do we know?

Rodney.

>> One in three women and one in four men in the United States take > vitamin pills. If you are among them, you may be doing more harm than > good. In a wake up call to the multibillion dollar vitamin pill > industry, a review of 67 randomized trials of vitamin pill effects on > life and health has found that taking vitamin pills may shorten life > (Cochrane Database of Systematic Reviews, Issue 1, 2008). Other > studies have shown that taking vitamin pills may increase risk for > cancers and heart attacks.> > This review of 232,000 adults showed that those taking beta-carotene, > vitamin A, C, and E and selenium gained no benefit over those who > took placebos or no pills. "The findings show that, if anything, > people in trial groups given beta-carotene, vitamin A and vitamin E > showed increased rates of mortality. There was no indication that > vitamin C and selenium may have positive or negative effects."> > The study was originally set up to see if antioxidant vitamin pills > and minerals prevent gastrointestinal cancers. It found no protection > whatever. Instead, an increased death rate of 16 percent was seen in > those taking vitamin A pills, seven percent with beta- carotene, and > seven percent with vitamin E. No increased death rate was seen in > those taking vitamin C or selenium.> > > > Dear Dr. Mirkin: Would you please explain how vitamin pills could > affect lifespan, as you reported in last week's issue?> > The issue of vitamin supplements is far from settled. > Most doctors take multivitamins themselves and recommend them to > their patients. However, I continue to believe that it is better > to get vitamins in whole foods than in pills.> Most vitamins are parts of enzymes that start chemical > reactions in your body. Each chemical reaction produces end products > that are changed by further chemical reactions from other vitamins to > other products that benefit your body. When you take a vitamin that > has been isolated from the hundreds of other substances found in > foods, that enzyme causes a chemical reaction that accumulates a > disproportionate amount of its end products. If the substance that > acts as an enzyme for the next chain of chemical reactions is not > available, you can accumulate end products that may be harmful. > For example, people who take niacin to lower cholesterol show > a marked elevation of homocysteine, a major risk factor for heart > attacks. Homocysteine levels are raised by a deficiency of B12, > folic acid and pyridoxine. When you eat your niacin in whole grains, > all of those components are present, along with many others whose > functions we may not yet understand. > Several of you asked for a link to the study I mentioned last > week; it has been added to the issue at > > http://www.mrw.interscience.wiley.com/cochrane/clsysrev/articles/CD007> 176/frame.html>