Rays raise controversy
Whatever your skin colour and ancestry, sunshine may be both healthy and damaging, say experts Exposure to sun combats vitamin D
Toronto Star - July 9, 2004 HOW TO STAY SAFE IN SUMMER
Sunshine's getting a bum rap these days and totally shunning its warming rays is unhealthy, a controversial doctor says. Contrary to established medical wisdom, Dr. Michael Holick says moderate sun exposure is good for you because it promotes production of vitamin D — especially in places like Toronto where people get next to no sun exposure in winter months.Holick says vitamin D has a host of important benefits besides the well-known facts: that it is good for bone health and helps prevent osteoporosis and rickets. It also supports cell regeneration, boosts the immune system and decreases blood pressure, he says, making it a front-line crusader against cancers, immune-system disorders and heart disease."This message to scare people out of the sun is very wrong," Holick says. "We've gone overboard and it is not doing a service to people who need to know that some exposure — moderate exposure — is healthy."The "hysteria" over sun hazards means many North Americans — especially those of middle-eastern, Indian or African ancestry — are now deficient in vitamin D, he says. Vitamin D is called the sunshine vitamin because skin makes it when it is exposed to sunlight. The need for vitamin D becomes more important for people with darker skin tones because they cannot easily produce the vitamin, Holick says. He also says the daily recommended dose of 400 IU is too low and that people need about 1,000 IU for optimal health. Holick cites studies that show up to 80 per cent of elderly African Americans in the Boston area are deficient in vitamin D by the end of winter. Another Boston area study found 42 per cent of African American women of childbearing age were vitamin D deficient by the end of winter. On average, he says 40 to 60 per cent of African American adults are vitamin D deficient. Although fortified milk is touted as a major source of vitamin D, Holick says he has conducted tests that found 50 per cent of milk products contain less than half the vitamin D they say they do and 20 per cent had next to none.In Canada, vitamin D deficiency in infants up to age 2 has skyrocketed, according to a recent study of rickets, released by the Canadian Paediatric Society last month. Ninety per cent of the near 100 babies treated for rickets were non-Caucasian. The society called for all infants — especially those who are breast-fed — to receive vitamin D supplements. Rickets can cause malformed bones, intense pain and convulsions, among other symptoms.But doctors like dermatologist Patrick Kenny, a spokesperson for the Canadian Dermatology Association, say Holick's advice is foolish and dangerous."No tan is a good tan," Kenny says. "People need to cover up, stay out of the sun and use a broad-spectrum sunscreen."Sun tanning causes several different types of skin cancer as well as premature aging and wrinkling, he says. He says a light-skinned person needs to be in the sun for just five minutes twice a week to make enough vitamin D, so there is no reason to fear deficiencies. He also says people can get sufficient vitamin D by drinking fortified milk products, eating certain fish or taking supplements.Though dermatologists have been pointing to the rise in skin cancers and urging people to cover up and use strong sunscreens for more than 15 years, most people still do not use the products correctly, if at all, he says. (Use sunscreen — applied generously and reapplied often — and limit exposure to the sun depending on the UV level. When it's 6 or 7, reduce your time in the sun and wear protection. When it rises above 8, take full precautions and avoid the sun between 11 a.m. and 4 p.m. And remember, sun damage is cumulative.) Holick says he does not advocate getting a tan — just moderate sun exposure based on how dark your skin is. He says people should use full spectrum sunscreens that block both UVB and UVA rays, after moderate sun exposure. But he says the medical establishment has it all wrong that any sun exposure is bad — especially when it comes to the most deadly form of skin cancer, melanoma, which usually appears on areas that are less likely to be exposed to the sun and rarely occurs on the face or hands. He cites findings presented at a 1995 U.S. Food and Drug Administration conference that melanoma is more common among people who do not get moderate sun exposure.And, he says, a study of people who worked outdoors for years — including farmers and navy personnel — found they were less likely to get melanoma than people who did not spend long periods of time outdoors. Studies show people who have many moles (more than 50 on their body) or a genetic history of melanoma, or who had a bad burn (defined as one that peels) in the first 30 years of life, face the highest risk. Melanoma makes up only 10 per cent of skin cancers, but is responsible for 85 per cent of skin cancer deaths. Holick says from the 1970s to the late 1990s, the widespread use of sunscreens that blocked only UVB and not UVA rays contributed to the melanoma increase. That's because when people were shielded from the UVB rays that cause sunburn, they were able to stay in the sun longer and actually increased their exposure to UVA rays, which Holick says cause most melanomas. Other forms of skin cancer — basal cell and squamous cell — are rarely fatal and easy to treat, he says.However, Kenny says there is no hard evidence that sunscreen use increased melanoma. He says melanoma started to increase in the 1930s, long before the use of sunscreens. Back then, one in 1,500 people got it; by the 1990s, one in 100 people did, he says. Toronto plastic surgeon and skin care expert Dr. Mahmood Kara says we need more public education about the needs of people with darker skin. Kara, whose ancestors originally came from India, says he can handle up to 20 minutes of sun exposure a day. After that, he puts on a sunscreen with an SPF of 15 because, if he doesn't, he can burn. But he recommends Caucasians use a sunscreen with a factor of 30 to 45. "I got a burn recently out at the zoo — I forgot my sunscreen and did not wear a hat and I have very little hair on my head," he says.He also stressed that darker-skinned people should consume many sources of vitamin D because they can more easily become deficient. People with darker skin need to know their own skin's limits, he says, and realize they can burn. By the time you feel a burn, the damage has already been done, he says.In his book, The UV Advantage, Holick lists a chart that says how much sun exposure people need based on where they live and their skin colouring.People in Toronto get no meaningful sun exposure at all between November and February, he says. However, from the hours of 8 a.m. until 11 a.m., from June through August, Torontonians with fair skin need to expose 25 per cent of their body to 10 to 15 minutes of sun, two to three times a week.During the same time and season, people with darker skin can handle exposing 25 per cent of their body to 30 to 60 minutes of sun two to three times a week, depending on their pigmentation, Holick says.
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