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Article by Men's
Health Magazine (a great health resource by the
way)
This article is provided for your information and use.
Frankly,
I didn't really want to die at age 37.
That was the first thought I
had three summers ago, when my dermatologist told me
that the small pink lump on my left cheek was, in fact,
skin cancer. He quickly went about assuring me that,
despite the funeral dirge playing in my head, death
wasn't really an option here. I had the mildest form
of the disease, basal-cell carcinoma, which hardly ever
causes long-term problems. What's more, removing it
would be a simple slice-and-stitch procedure. And that's
just what it was. In the end, the root canal I'd had
2 months earlier was probably more of a near-death experience.
That said, ever since that moment,
I--like so many guys nowadays--have become far more
conscious of protecting myself from the sun. I slather
sunscreen on my fast-burning Irish skin and outfit myself
in a series of grimy baseball caps (my fedora phase,
thankfully, has passed). Having cheated death at age
37, I'm not about to let it win at age 47.
There's just one hitch: My attempts
to save my skin may ultimately cost me my life. At least
that's the warning a group of researchers is giving
sun-phobics like myself. They're suggesting we've grown
dangerously leery of the sun and, specifically, that
we need more of the ultraviolet vitamin, vitamin D.
As evidence, they point to an alarming number of people--particularly
those living in the northern part of the United States,
and those with dark skin--who are running close to "E"
when it comes to D.
Sun Spotting
In 2002, for example, a study
of otherwise healthy 18- to 29-year-olds in Boston found
that one-third had significantly low vitamin D levels
by the end of the winter. A recent article in the journal
Nutrition Reviews, which looked at five separate studies,
concluded that "prevalence of vitamin D insufficiency
is higher than anticipated in North America." Meanwhile,
one noted expert on bone and calcium believes that the
problem is even bigger than that. "I admittedly
have a liberal standard," says Robert Heaney, M.D.,
of Creighton University in Nebraska, "but I estimate
that as many as 80 percent of people in the United States
don't get enough vitamin D."
Now, granted, "You need
more vitamin D" sounds like what your grandmother
might say if she were named Surgeon General (right after
she proclaimed beets the national vegetable). But there's
reason to pay attention, since researchers believe that
a lack of D--a substance that helps our bodies use calcium
and is crucial to bone strength--could be behind much
of what ails us here at the dawn of the 21st century,
including heart disease, colon cancer, and prostate
cancer. Indeed, a 2002 study in the journal Cancer speculated
that vitamin D undernourishment may lead to more than
23,000 cancer deaths each year.
"I think this is a major
unrecognized epidemic in the United States," says
Michael Holick, M.D., a researcher at Boston University
medical center and the most high-profile member of the
vitamin D research community. "It affects children
and adults of all ages, all races, and both sexes. It's
very significant."
The Dividing Line
The way God drew it up, getting
enough vitamin D ought to be a cinch, since the process
is as unconscious as breathing. When you're outside
in the sunlight, UVB rays from the sun activate an enzyme
in your skin. Presto, vitamin D is created and goes
to work in your body.
Unfortunately, in practice several
things can interfere with the process. First is geography.
The farther you are from the equator, the less direct
the sunlight is, and the weaker the UV rays become.
Above 42? north, for example--picture a line stretching
roughly from Boston to northern California--it's difficult
for many people to produce vitamin D during the winter.
African-Americans, Latinos, and others with dark skin
are at a further disadvantage, since their pigmentation
limits the UV light they can absorb and slows vitamin
D synthesis.
The final obstacle in vitamin
D production is, or at least can be, the environment--the
cause of the last big vitamin D crisis, in the early
1900s. As the industrial revolution kicked into high
gear, more people moved to the cities and hunkered down
in dark, dank tenements; meanwhile, pollution from bustling
factories clouded the skies. The result was far fewer
UV rays touching people's skin, and a lot more vitamin
D deficiency. "At the turn of the last century,"
says Dr. Holick, "more than 80 percent of the kids
in Boston had rickets."
Moo Juice
While fortifying milk with vitamin
D eventually solved the rickets problem, it may have
given us a false sense of security. Research has shown
that our milk supply, for all the trust we put in it,
is remarkably unreliable. A 1992 study published in
the New England Journal of Medicine showed that, of
42 milk samples tested, 26 contained less than the 400
international units (IU) of vitamin D per quart listed
on the label. Some of the skim milk tested contained
no D at all. In 2001, Cornell University researchers
analyzed 648 samples of milk sold in New York State
and found that 46 percent were underfortified.
But even if milk came as advertised,
it still might not cover our bodies' needs. While the
current recommended daily intake is 200 IU for adults
up to age 50, there's a growing consensus that we need
five times that--1,000 IU--to keep our blood levels
where they should be. (An editorial in the New England
Journal of Medicine several years ago argued for just
such an increase.) And that's nearly impossible to get
solely through diet, particularly since cold-water fish
is the only food naturally high in D. As Dr. Holick
puts it, "You'd have to take a multivitamin, drink
two glasses of milk, and eat salmon every day just to
begin to satisfy your vitamin D requirement."
Sundry Facts
On a recent morning--a warm,
sunny one, it's worth noting--I am sitting in Dr. Holick's
office at BU medical center. Lean and wiry, with shaggy
white hair and lively blue eyes, Dr. Holick has been
studying vitamin D since he was a graduate student at
the University of Wisconsin 30 years ago. Lately, he's
also become one of the most controversial vitamin D
researchers. Earlier this year, just prior to the publication
of his new book, The UV Advantage, Dr. Holick was asked
to resign from BU's dermatology department by the chairwoman,
Barbara Gilchrest, M.D.
"She'd been e-mailing me
for more than a year, saying her dermatologist friends
had been questioning how I could be a professor of dermatology
and suggest that people be exposed to some sunlight
for their health," says Dr. Holick, who still holds
several positions at the university. "Then, in
February, she told me she would like me to resign. Which
I did."
Dr. Gilchrest declined to be
interviewed for this story, but when one newspaper asked
what she thought of Dr. Holick's recommendations, she
answered, "I read better things in ladies' magazines."
Her criticism was echoed by the American Academy of
Dermatology, which likened the advice to "smoking
to combat anxiety." (Dr. Holick's critics also
say that he accepts money from the indoor-tanning industry.
He doesn't dispute the charge, but claims the amount
is small and comes with no conditions.)
In a way, it's tough to blame
dermatologists for their hard-line zeal. In 1980, roughly
400,000 cases of skin cancer were diagnosed in the United
States; this year it will be more than a million. Little
wonder that the U.S. government recently added UV radiation
to the list of known human carcinogens.
Dr. Holick tells me he doesn't
deny that skin cancer is a problem--in fact, he says
that after a few minutes in the sun, people should cover
up or use sunscreen. But he also believes that the zero-tolerance
approach of many dermatologists could be just as dangerous.
Two large population-based studies seem to lend credence
to his concern. A few years ago, a NASA physicist named
William Grant, Ph.D., noticed that residents of New
England were 1 to two times more likely to get prostate,
colon, or breast cancer than those living in the Southwest.
Intrigued, Grant began comparing the UV levels in 500
U.S. cities and counties with the rates of cancer in
those areas.
"I found a correlation between
lower UV levels and a higher incidence of 12 different
types of cancer," says Grant, who launched the
San Francisco-based Sunlight, Nutrition and Health Research
Center to further study vitamin D. More recently, Grant
redid his study (which was published in the journal
Cancer), this time controlling for other cancer risk
factors, such as smoking and alcohol intake. The new
research, which hasn't yet been published, confirmed
his findings.
A similar geographic link has
been found between sun exposure and multiple sclerosis:
Cases of MS in the United States increase the farther
north you go. And a new U.K. study found that those
with skin cancer have half the rate of MS of those without
cancer. Grant says the link is inescapable. "I
estimate that half of the 400,000 with MS in the United
States would not have MS if they had the same UVB doses
as those living in the southern states."
If vitamin D were on trial in
a court of law, Grant's findings would be circumstantial
evidence--compelling, but not enough to convict. A stronger
case can be made for the connection between vitamin
D and bone health. Not only does research show that
low levels of D can increase your risk of osteoporosis
by as much as 300 percent, but new research also is
finding a link to unexplained bone pain. A study from
the Riyadh Armed Forces Hospital in Saudi Arabia found
that 80 percent of back-pain sufferers were light on
vitamin D.
Less concrete--but more alarming--is
exhibit B of D's relationship to cancer. Lab studies
have shown that cancer cells have difficulty growing
when D levels are normal; meanwhile, a study published
last December in the Journal of the American Medical
Association found that those with diets high in vitamin
D were 40 percent less likely to develop potentially
cancerous colon polyps.
Researchers have also discovered
a link between vitamin D and heart health. Studies have
shown that the farther you live from the equator, the
higher your blood pressure is likely to be, and that
people tend to have lower blood pressure during the
summer, when UV rays are stronger. (The hormone that
controls BP is regulated by vitamin D.) And a study
last year in the Journal of the American College of
Cardiology found that low vitamin D levels may be a
factor in congestive heart failure.
Sun Rise, Sun Set
Still, the idea of vitamin D
as a possible panacea has some people, including many
dermatologists, skeptical. James Spencer, M.D., director
of dermatologic surgery at the Mount Sinai Medical Center
in New York City, says Dr. Holick and his colleagues
remind him of the late Linus Pauling, the Nobel Prize-winning
researcher who became obsessed with the idea that vitamin
C could ward off everything from colds to cancer. "Dr.
Holick got religion on vitamin D the same way Dr. Pauling
got it on vitamin C," says Dr. Spencer. "It's
a very appealing notion: Just take this pill, or spend
more time in the sun, and everything will be fine. But
come on, is life ever that simple?"
Vitamin D researchers, ironically,
argue that it's the dermatologists who are oversimplifying
things. "A tendency we all have is to focus on
the disease in our specialty," says Dr. Heaney.
"The dermatologists have looked at the rise in
melanoma and panicked. But they aren't looking at the
whole human being."
Dermatologists have also exaggerated
the actual risk that skin cancer poses, say D experts.
They note that, while skin cancer is the most frequently
diagnosed cancer in the United States, more than 90
percent of cases are either basal-cell carcinoma or
squamous-cell carcinoma. Both are relatively harmless
if detected early. Granted, nearly 8,000 deaths per
year from melanoma are not to be dismissed, but from
a public-health standpoint, that makes skin cancer less
of a problem than vitamin D deficiency is, says Bruce
Hollis, Ph.D., a vitamin D researcher at the Medical
University of South Carolina. "I tell my medical
students that if I were going to have cancer, I'd rather
have basal-cell carcinoma than breast cancer, colon
cancer, or one of the other cancers linked to vitamin
D deficiency."
Sunshine of My Life
So in the end, are we simply
left with a grim choice--either dying of too much sun
(skin cancer) or too little (prostate cancer, MS)? Not
necessarily. In the short term, those most at risk--African-Americans,
people living in the northern part of the United States,
the elderly--can get a blood test to see whether they
have adequate levels of vitamin D. We can also be judicious
about which parts of our bodies get exposed to the sun:
Since basal- and squamous-cell cancers most often appear
on the face and ears, Dr. Holick suggests protecting
those areas with sunscreen, while still exposing your
arms and legs.
Of course, the ultimate solution
would be to find some way to get the vitamin D we need
while limiting our exposure to the sun. And those possibilities
exist--from broader, more reliable fortification of
the food supply to more powerful D supplements. (Right
now, most multivitamins contain just 400 IU, even though
toxicity only becomes a concern at 10,000 IU and above.)
Or perhaps there's some other way.
"I'm a fan of Stanley Kubrick
and the film 2001: A Space Odyssey," Dr. Holick
tells me as we sit in his office. "And in there,
he has the astronauts being exposed to simulated sunlight
to make vitamin D. I think that one day indoor lighting
will be developed so you could actually be exposed to
small amounts of UVB rays to get your vitamin D."
Vitamins from the lights?
Maybe our future isn't as dark as it seems. But in the
meantime, I've never been happier that I like salmon.
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