Topic: Vit D-lack of Rickets, Autism?, Depression ?
So we are safe now from skin cancer but our children are getting rickets..
Shun the sun, lose vitamin D
The "sunshine vitamin" might not be a silver bullet in holding off cancer, but the human body needs copious doses
Wednesday, November 14, 2007
The Oregonian Staff
Vitamin D, the "sunshine vitamin," has made headlines as a potential cancer fighter. New studies have pitted specialists such as endocrinologists and immunologists, who call for limited sun exposure, against dermatologists, who worry about skin cancer. And Oregon's northern latitude has local experts at the forefront of the debate.
Researchers think vitamin D deficiencies, long linked to bone disease, might also play a role in autoimmune diseases, cancer and some neurological disorders.
A recent long-term study by the National Cancer Institute analyzed vitamin D and concluded its effect on most cancers was minimal. Vitamin D's proponents zeroed in on the fact that blood levels of the vitamin were tested only once in the study. In fact, levels can vary widely because of seasonal and dietary changes.
"No single study can provide a definitive answer," says Tomasz Beer, a hematologist and oncologist at Oregon Health & Science University who studies vitamin D.
Skin makes vitamin D when sunlight hits it. The vitamin can also come from oily fish such as salmon, or dairy products fortified with vitamin D, a practice that started in the 1930s to prevent rickets. Or you can take a pill.
But since 1989, public health officials worried about skin cancer have warned against unprotected sun exposure. Now, a resurgence of rickets has prompted a re-examination of vitamin D deficiencies.
Those at particular risk include exclusively breast-fed infants, the elderly, and dark-skinned people who live at latitudes where the sun is weaker. Pigmentation, which protects against damaging ultraviolet rays, also blocks vitamin D production.
Jon Hanifin, a professor of dermatology at OHSU, warns against sun exposure. "It's dangerous to encourage fair-skinned people to go out and get sun exposure, especially in midsummer," he says, so he encourages supplements. "I take 1,000 units a day myself."
What do we need to know about vitamin D? The Oregonian spoke to several experts who gathered in Portland last month for a conference on vitamin D:
Endocrinologist Michael McClung, founding director of the Oregon Osteoporosis Center "When we started doing research in the 1970s, women in the northern U.S. had a higher incidence of vitamin D deficiency than those at southern latitudes. But now people who live in Houston or Miami are on par with Portland. We believe that comes from sunscreen use. Number 8 SPF obliterates the body's ability to manufacture vitamin D.
"Our studies show that approximately 60 percent of 60-year-old women, and 80 percent of 80-year-old women have a vitamin D deficiency. As people age, they metabolize vitamin D differently.
"The recommended dietary intake is . . . woefully inadequate and came from the 19th century. . . . It's not nearly enough to keep bone loss from occurring in older adults.
"For older people, vitamin D deficiency is a major risk factor in accelerated bone loss. It also causes muscle weakness, which causes falls. Weak muscles and fragile bones are a devastating combination.
"Being in the sun a modest amount is reasonable. When I play golf or go to the beach, depending on the time of year, I'll be in the sun for 30 minutes without sunblock, and then put it on. The recommendations to totally avoid the sun are an overreaction."
John Cannell, psychiatrist, Atascadero State Hospital in California, founded and runs the nonprofit Vitamin D Council (www.vitamindcouncil.com)
Cannell co-authored a 2006 paper in the journal Epidemiology and Infection after a flu epidemic swept through the 1,200-patient Atascadero State Hospital. His patients, who took vitamin D supplements, didn't get the flu. In recent months, Cannell has created an Internet firestorm by linking vitamin D deficiency and autism.
"Autism has increased dramatically since the 1980s. At the same time, doctors started encouraging people to avoid the sun. So if vitamin D is involved, the epidemiological tracks are clear-cut. Animal studies show vitamin D deficiency during pregnancy causes brain damage in the offspring. And a recent study from Cambridge University showed a distinct urban versus rural gradient in the incidence of autism. Recently, the Centers for Disease Control and Prevention reported the autism rates from 14 states. The state with the highest prevalence, New Jersey, is the second-most northern state in the study. Alabama, with the lowest prevalence, is the most southern of the 14 states surveyed.
"Parents connect immunizations and autism, because their kids get the shots between 18 months and 2 years, around the time they get the diagnosis. That's also the time they go from vitamin D-rich formula or milk to food and juices that contain almost none.
"In 1989, when we were told not to go in the sun, we didn't hear one word about getting vitamin D. That's radical advice for a species that has evolved in the sun to suddenly say, 'Don't go near it.' I blame doctors -- I blame myself.
"What do parents have to lose if they put their toddlers and young children on 1,000 to 2,000 daily units of vitamin D, depending on body weight? They don't lose anything. They help their kid make stronger bones. If I'm wrong, the only thing that will happen is that they get more vitamin D.
"If you put on your bathing suit in the summer in Oregon, your body makes 200 times more vitamin D than the government says you need every day. Whether it's nature, or God or whatever you believe in, why would there be a system in our skin that makes so much vitamin D so quickly? Probably nature set this up for a good reason. What did our mothers, and their mothers before them, say? Drink your milk, and go play outside."
Cindy Reuter, naturopathic physician, licensed acupuncturist, and registered dietitian at Providence Integrative Medicine
"We see a lot of folks with cancer and a lot with chronic pain. Vitamin D turns out to have an important role in musculoskeletal health.
"When someone comes to see me, I try to treat the person as a good holistic thinker. Vitamin D is high on my list for depression, cancer, seasonal affective disorder, fatigue, musculoskeletal pain. I wonder about their ability to make vitamin D.
"I worked hard on my tan this year. I got a good dose of sun. It is the first fall in history that I'm not feeling that 'uunph' I get when the days get shorter. I'm (only one person), so I'm not drawing any conclusions.
"Of course melanoma is something we need to be concerned about. But there are studies that show that when you have a higher incidence of non-melanoma skin cancers, you have a reduced risk of internal cancers. That's interesting data.
"But I want to caution people. Vitamin D is safe stuff, but it's not risk-free for everybody, including some people on certain chemotherapy. Get professional advice."