From Medscape Medical News
Is too little sun exposure leading to vitamin D deficiency?
processing....
|
|
|
|
|
|
|
|
|
|
Atascadero, CA - While the American Academy of Dermatology remains steadfast that prescribing sun exposure to promote vitamin D is irresponsible, the US-based Vitamin D Council charges that dermatologists may be liable on a causation basis if they continue to risk patient health by advising the elimination of what they say is a fundamental health benefit.
"If I were a dermatologist and knew the vitamin-D literature, I would be very nervous," Dr John Cannell, executive director of the Vitamin D Council, told rheumawire . "When you intubate a patient, you are taking control of the system and you have an affirmative duty to maintain that system. When dermatologists advise people to stay out of the sun, they are effectively taking control of the system and preventing people from obtaining the many health benefits of vitamin D."
In a statement issued this spring, the American Academy of Dermatology estimated that more than 100¿000 people in the US will be diagnosed with melanoma this year—a number that represents a 10% increase in new cases from 2004. According to the academy, melanoma will claim approximately 8000 lives this year alone. As a result, dermatologists are recommending that instead of seeking the sun, anyone concerned about getting enough vitamin D supplement a healthy diet with vitamins and fortified foods and beverages.
|
|
|
|
|
|
Dr Clay Cockerell (Source: CME.md)
|
|
|
|
"While many health issues are complex and involve multiple factors, we know that ultraviolet light is the primary cause of skin cancer, and avoiding excessive exposure to the sun and other forms of ultraviolet radiation is the solution," Dr Clay Cockerell, president of the American Academy of Dermatology, told reporters.
"Individuals who seek the sun are intentionally putting their health at risk. When you are enjoying yourself outdoors, be smart by taking steps to protect yourself—seek shade whenever possible, wear sunscreen, and cover up with a wide-brimmed hat, long sleeves, pants, and sunglasses. Also, avoid tanning beds," Cockerell added.
More than 100 ¿ 000 people in the US will be diagnosed with melanoma this year.
But Cannell says, "Statements such as these scare people into fearing to ever let a ray of sunlight touch their skin, even though it is well documented that vitamin D through sun exposure can have a positive effect on just about every disease listed in Harrison's Manual of Medicine." Cannell argues that vitamin D reduces the risk of autoimmune diseases as well as a variety of internal cancers and heart disease and may also be linked to diminishing the effects of age-related memory problems. He says that it is almost impossible to consume adequate vitamin D through diet alone and while supplements are an important alternative, most people don't get the recommended amount.
Statements such as these scare people into fearing to ever let a ray of sunlight touch their skin.
Concern over inadequate vitamin D levels was also raised in research presented at the European League Against Rheumatism 2005 meeting in Vienna, Austria this past June [ 1 ]. Investigators reported that more than half of postmenopausal women worldwide have insufficient vitamin-D levels.
"It is very alarming how many women do not have enough vitamin D to reduce the loss of bone during menopause," lead author Dr David Hosking (Nottingham City Hospital, UK) told the press at the meeting. "These study results clearly show that, regardless of age, geographic region, or latitude, many women with osteoporosis are not getting enough vitamin D."
Recommended daily vitamin D intake as described by Hosking et al
|
g)
Hosking and his team conducted two similarly designed cross-sectional studies of more than 1500 participants from North America and 1200 others from around the world. The mean age was 71 years in North American subjects and 68 in the international group. The researchers obtained serum 25-hydroxyvitamin D intact parathyroid hormone levels and a chemistry panel. They also conducted a questionnaire assessing factors influencing vitamin-D status. They found that vitamin-D inadequacy is common in osteoporotic women in all regions of the world, regardless of age, latitude, or season.
"I am surprised by the results in places like Florida and Asia, where people are exposed to plenty of sunshine," Hosking told reporters at EULAR. "However, in the Middle East, where it is too hot to go outside and where many women are completely covered, you can see why their levels of vitamin D would be low." He added that these studies dispel the myth that women with osteoporosis living in sunnier latitudes do not have to worry about vitamin D. "Clothing, use of sunscreen, and avoidance of sun exposure, particularly in hot climates, could explain the high prevalence of vitamin-D inadequacy observed in the study."
The current caveman existence of many in our society is abhorrent. They wake up in their house, put sun block on, get in their car—perhaps in a covered garage—and drive to another underground garage at work.
Hosking said that it is critical that women find ways to get more vitamin D to ensure that they receive the full benefits of therapy, ultimately enhancing bone strength and preventing fractures. He recommends time outdoors—as little as 15 minutes at a time—along with dairy products included as part of a healthy diet.
Cannell concurs that even short periods in the sun can make a big difference, but he points out that people with darker skin tones will require more. But most dermatologists disagree; Cockerell says, "Even when wearing sunscreen, the average person receives enough incidental ultraviolet exposure through daily activities to achieve recommended vitamin-D levels." He argues that people should not increase their exposure to either natural or artificial UV light because there is a high risk of developing skin cancer from repeated exposure.
Cannell retorts that dermatologists are overreacting. "The current caveman existence of many in our society is abhorrent," he said. "They wake up in their house, put sunblock on, get in their car—perhaps in a covered garage—and drive to another underground garage at work, eat lunch indoors, and may never see the light of day. It isn't natural or healthy to live that way."
Cannell says that, without question, more research must be done. "But while these studies are being conducted, does the reader want to be vitamin-D deficient?" He asks. "I sure don't."
Source
Authors and Disclosures
Author(s)
Allison Gandey
Allison Gandey is a journalist for Medscape. She is the former science affairs analyst for the Canadian Medical Association Journal. Allison, who has a master of journalism specializing in science from Carleton University, has edited a variety of medical association publications and has worked in radio and television. She can be contacted at agandey@webmd.net.
Medscape Medical News © 2005
