Vitamin D, Skin Cancer, Sunlight
Even Taking Off Your Clothes Is UselessBy Dr. Gifford Jones
If you asked anyone to stand outside naked during the winter months from sunrise to sunset, they would think you’d gone bonkers. But even if willing to be arrested for doing it, they would still not receive enough sunshine to produce vitamin D. Today we’re constantly urged to keep out of the sun for fear of skin cancer. But most people are unaware that too little vitamin D from the sun may increase the risk of cancer, heart disease and diabetes.
Dr. Catherine Gordon, a pediatrician at The Harvard Medical School, recently reported a shocking finding to The Endocrinology Society. Gordon and her colleagues tested the vitamin D levels of 307 teenagers between 11 and 18 years of age. 24 per cent of these adolescents of both sexes were deficient in vitamin D.
Dr. Glenn Braunstein, professor of medicine at The University of California, adds “This is a wake-up call”. He says, “It’s now apparent that not only the house bound or elderly in nursing homes are getting insufficient sunlight”.
So why is it so hard to get adequate amounts of sunlight? It depends on where you live. For cities at a latitude above 35 degrees north which includes Boston, Philadelphia and all of Canada, vitamin D production ceases from October to the end of February.
During these months sunlight is filtered at a more oblique angle through the atmospheric ozone layer. This decreases the ultra-violet radiation that triggers vitamin D production.
Early in the 1900s researchers discovered that deficiency of vitamin D caused rickets. It’s a childhood disease in which bones fail to develop normally. The result is bowed-legs and knock-knees.
Vitamin D’s primary function is to maintain normal blood levels of calcium by helping adults and children absorb calcium from food. This prevents osteoporosis (brittle bones) and tooth loss. The current epidemic of osteoporosis can be attributed in part to a deficiency in this vitamin.
Dr. Michael Holick, a world authority on vitamin D at Boston University, believes vitamin D’s greatest strength may be its role as a cancer fighter. Studies show that people living in higher latitudes have increased risk of dying from almost all types of cancer, but particularly breast, colon, prostate and skin cancer. If this is true, Dr. William Grant, an environmental scientist, estimates that every year 24,000 Americans die due to insufficient sunlight.
Vitamin D may also play a role in preventing heart disease. We know that people with thin bones often have deposits of calcium in their arteries. This may happen because a lack of vitamin D causes the body to churn out extra parathyroid hormone. It, in turn, pulls calcium out of bone and some ends up in coronary arteries, setting the stage for heart attack.
Today diabetes has reached epidemic proportions. Lifestyle diabetes, type 2, is usually due to obesity. But the risk of getting juvenile diabetes, type 1, is increased if there’s a deficiency of vitamin D since it’s needed in the production of insulin.
Finally vitamin D may help to fight osteoarthritis, the wear-and-tear type, that causes so much disability and suffering. Boston researchers studied 75 arthritic knees for 10 years. They discovered that osteoarthritis was three times more likely to become worse in those who had average or lower vitamin D levels.
The take-home message is to ensure you take adequate amounts of vitamin D at all times of the year. The best sources of vitamin D in food are fatty fish, egg yolks, liver, butter, cheese and along with milk, cereals and margarine that are fortified with D.
Don’t become paranoid about the sun. In moderation it’s a good source of vitamin D. Remember that 10 minutes of daily exposure during the summer months will help store vitamin D for the winter ones.
But what about those winter months from October to February? Since many of us are not snow-birds that fly south every winter, taking a vitamin supplement of 800 units a day is a sound insurance policy to protect us from the lack of this much neglected vitamin.(0) Reader Feedback | Email Article | Email Us | Print friendly
Dr. Gifford Jones Bio
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W. Gifford-Jones M.D is the pen name of Dr. Ken Walker graduate of The Harvard Medical School. He’s been a ship’s surgeon, hotel physician and family doctor and later trained in surgery at McGill in Montreal, University of Rochester N.Y. and Harvard. His medical column is published by 60 Canadian newspapers and several in the U.S. He is the author of seven books. Dr. Walker has a medical practice in Toronto. His Web site is: http://www.mydoctor.ca/gifford-jones