Last week, I began to answer a reader’s question about a new study
published in the Archives of Internal Medicine, a semimonthly professional
medical journal published by the American Medical Association. It reported
on the potential unhealthy and even dangerous effects of some vitamins for
women ages 55-69.

The study alleged that women taking multivitamins or supplements of
iron, vitamin B-6, zinc, magnesium, folic acid or copper had at least a 2.4
percent increased chance of death. Calcium, however, reduced the risk of

Since the media hysteria over the initial reporting of this study, a
host of health and nutrition experts have rebutted it as largely junk
science. My own rebuttal in Part 1 noted how it was based upon inadequate
research, faulty statistics and no clinical verification or medical
investigation. It was unjustly founded upon only three self-reporting and
limited health surveys given over an 18-year period.

One of the biggest reasons for calling it into question is that in
2002, The Journal of the American Medical Association itself shocked the
medical world by publishing a study that recommended all adults take a
multivitamin supplement for the purpose of helping to prevent chronic
diseases. The recommendation was based upon the review of scientific and
medical studies from 1966-2002 in which those who did not take supplements
were at increased risk for heart disease, cancer and other chronic diseases.

The new, negative vitamin study’s lead author himself, Dr. Jaakko
Mursu of the University of Eastern Finland and the University of Minnesota,
confessed to Reuters that the three surveys don’t prove vitamins and
supplements are harmful, just that they may not be so helpful as we
assumed or they are marketed to be.

Mursu summarized: “I would conclude that supplements are not protective against chronic diseases. In some cases they may be harmful, especially if used for a long time.”

But that is not a health revelation; it’s old news. We’ve long known
that vitamins can become toxic when taken at heightened levels. Most
micronutrients consumed in large amounts can be detrimental.

For example, Mursu’s study focused particularly on an increased risk
of death for those women who take iron supplements. But as CBS News medical
correspondent Dr. Jennifer Ashton pointed out, we already knew that for
those “with certain types of blood disorders, excessive iron can be
dangerous to the heart and liver.”

Moreover, ABC News recently reported that by only doubling the
government’s daily recommended dosage of vitamin A in the form of retinol,
one can increase the risk of liver damage and birth defects. And excessive
doses of vitamin C (often taken for colds) can cause gastrointestinal

A study led by the chairman of the Glickman Urological and Kidney
Institute at the Cleveland Clinic reported that men taking supplemental
vitamin E may be increasing their risk for prostate cancer by up to 17

Similarly, in a study by Columbia University, women with early-stage
breast cancer who took carotenoids (such as vitamin A and beta carotene) had
a higher risk of dying from breast cancer than women who did not take them.
On the other hand, women who took supplements of either vitamin C or vitamin
E had a lower risk of cancer recurrence over five years than those who

Another important consideration with excessive vitamin consumption
is that in order to compensate for lack of nutrition, many food producers
have fortified foods and beverages with an overabundance of vitamins and
minerals. So if one already is taking supplements, it isn’t difficult to see
how overload can occur.

At the same time, we must never forget that there are those who
genuinely need additional nutrient supplements – such as pregnant women,
who need folic acid (to prevent neural tube defects), vegetarians, who often
need more iron, and those who want to slow down osteoporosis with calcium

Because nutrients are both needed in the undernourished and
potentially harmful for those who overly consume them, balanced health
enthusiasts and practitioners don’t prescribe a one-size-fits-all
supplement; they consider gender, age, genetics, diet and other health
habits and stats while also reviewing a complete blood count that accurately
measures nutrient levels.

Only after a complete holistic review should one be advised as to
what to supplement or avoid, and that prescription should be led by
improvements to one’s diet.

As Connie Diekman, director of nutrition at
Washington University, said, “Supplements should be viewed as ways to boost
intake when food does not meet need.”

The potential helpful and harmful effects of dietary supplements are
more proof that we should not check in our brains at the door of health.
Double-check the facts. Ensure that the data are backed by other reliable
studies. Don’t just swallow everything the news conveys, especially when so
much today is reported to scurry and rally viewers and readers.

The point is, whether it’s multiple vitamins or junk food, we need
to be more mindful of what we are putting in our bodies and what the
long-term effects of such consumption might be. At the very least, until you
consult with your health practitioner, don’t surpass recommended daily
dosages of vitamins. Most of all, remember that nothing replaces a
well-balanced diet. An excellent resource is the University of California,
Berkeley’s “Wellness Foods A to Z.”

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