http://www.insidebayarea.com/columns/ci_16147481
Barnidge: Don't look now, but you're vitamin D deficient
By Tom Barnidge
Contra Costa Times columnist
Posted: 09/22/2010 05:39:39 PM PDT
PEOPLE PUT off physical exams for the same the reason they postpone servicing their cars. Anytime a doctor examines your undercarriage, there is a chance he will find something wrong.
Maybe he will discover that your heartbeat has a murmur. Or your blood pressure is outside acceptable norms. Perhaps your cholesterol count's too high, your iron count too low or your blood sugar is a concern.
You can imagine my dismay when I recently cleared all the those hurdles only to hear the doctor pronounce: "You are vitamin D deficient."
Nobody told me that would be on the test. Since there were no problems with the rest of the alphabet, I said, it seemed like a minor concern.
"Vitamin D deficiency," he said, "has been linked to diabetes, cancer and tuberculosis."
Oh.
The doctor went on to explain that studies indicate about 65 percent of all Bay Area residents are deficient in vitamin D. Among his patients, the number is closer to 75. That's a lot of people coming up short on their report cards.
The high incidence is partly a product of our geographic location -- northern latitude, short winter days and frequent foggy weather. The sun's ultraviolet rays naturally stimulate the body to produce vitamin D, but those are in short supply when sun is blocked or sits low on the horizon.
Even during the summer, the benefits are diminished if you use sunscreen because it blocks more than 90 percent of UV rays. Of course, if you don't use sunscreen, you might get skin cancer. It's always something.
Many medical experts have expounded on the vitamin D problem recently, notably the Harvard School of Public Health, which posted a lengthy report online earlier this year that begins with this warning: "If you live north of the line connecting San Francisco to Philadelphia, odds are that you don't get enough vitamin D."
If you live on the line, flip a coin. You might get lucky.
The Harvard report cites enough studies to give anyone pause:
Of 50,000 healthy men monitored for 10 years, those with vitamin D deficiency were twice as likely to have heart attacks.
In a 30-year study of more than 10,000 Finnish children, those who received vitamin D supplements during infancy had a nearly 90 percent lower risk of developing Type I diabetes.
A study of 340 Japanese schoolchildren showed those taking daily vitamin D supplements contracted 40 percent few cases of Type A influenza.
Research on 40,000 elderly people, mostly women, found that high intakes of vitamin D reduced hip and non-spine fractures by 20 percent.
Medical researchers link vitamin D deficiency to osteoporosis, rickets, heart disease, cancer, multiple sclerosis, tuberculosis, infectious diseases and asthma. I'm planning to give supplements to my dog to see if they keep away fleas.
The best way to increase your intake, apart from sunshine, is through diet -- dairy products, soy, breakfast cereals and fatty fish such as salmon and tuna -- or with supplements. Dr. Daniel Bikle, professor of medicine at UC San Francisco, writing in "Trends in Endocrinology and Metabolism," says that "2,000 units a day would be adequate for most healthy adults."
Be aware, though, that too much of a good thing is bad. Excessive amounts of vitamin D can be toxic.
It makes you nostalgic for the good old days, when all we had to worry about was secondhand smoke and cancer-causing cyclamates.
