Vitamin D is Called the Sunshine Vitamin for Good ReasonMichael F. Holick, PhD, MDProfessor of Medicine, Physiology and BiophysicsDirector of the General Clinical Research CenterDirector of the Vitamin D, Skin and Bone Research LaboratoryDirector, Biologic Effects of Light Research CenterBoston University Medical Center
http://www.vitamindcouncil.org/scientists.shtml Lists of scientists on Vitamin D research. Holick is one of these.
Vitamin D is not a vitamin but a hormone. It is unique in that it is made in the skin as a result of exposure to sunlight. Photosynthesis of vitamin D has been occurring on earth for more than 750 million years. Some of the earliest life forms that were exposed to sunlight for their energy requirement were also photosynthesizing vitamin D. Both children and adults have in the past depended on adequate sun exposure to satisfy their vitamin D requirement. It is well documented that at the turn of the last century upwards of 80% of children in the industrialized, polluted cities of northern Europe and northeastern United States suffered from the devastating consequences of vitamin D deficiency rickets. The skin has a large capacity to make vitamin D. Exposure of a person in a bathing suit to a minimal erythemal dose of sunlight, which is typically no more than 15-20 minutes on Cape Cod in June or July at noon time, is the equivalent to taking 20,000 IU of vitamin D orally. It is now well documented that in the absence of any sun exposure 1,000 IU of vitamin D3 a day is necessary to maintain healthy levels of 25-hydroxyvitamin D in the circulation. An analysis of the NHANES III data has demonstrated that neither children nor adults are receiving an adequate amount of vitamin D from their diet or from supplements. ... http://www.vitamindhealth.org/?p=3#more-3
QUESTIONS FOR DR. MICHAEL HOLICK
Interview by DEBORAH SOLOMON
Published: March 15, 2010
In your new book, “The Vitamin D Solution,” you argue that we have become a culture of sun phobes who fear exposure to direct sunlight and slather on too much sunscreen, which you believe has caused a national epidemic of vitamin D deficiency.
Why do they say that?
They are heavily invested, I think, with the cosmetics industry. The American Academy of Dermatology just had their annual meeting in Miami Beach. It was huge. Many of the major cosmetic companies were there, and they were spending thousands of dollars just to be out there and promote their products to the dermatologists.
Why would the anti-sun academy hold its annual meeting in Miami Beach, the sun capital of the East?
That kind of says it all. They still seek the sun, just like everyone else.
How long does one need to stay in direct sun to absorb 2,000 I.U. of D, your ideal daily dose?
You don’t absorb it. You make it. In the spring, I recommend about 15 to 30 minutes on your arms and legs two to three times a week.
What if you would rather be dead than walk around New York in gym shorts? Why is exposing your legs so important?
There’s the rule of 9s. You have about 18 percent of your skin surface on each of your legs. Your face is only 9 percent; we never recommend you expose your face. You should always protect it with either sunscreen or an appropriate hat.
In 2004, you were fired from Boston University’s department of dermatology by Dr. Barbara Gilchrest, who was head of the department.
She called me into her office and said that she couldn’t have somebody in her department recommending sun exposure.
At the time, she also questioned whether your findings had been compromised by money you received from the tanning industry. You received research money from the Indoor Tanning Association.
That’s not true. The money came from the UV Foundation, a nonprofit arm of the Indoor Tanning Association.
You’re still at Boston University, where you run the vitamin D lab, right?
We’ve been looking at prostate and colon cancer and showing that if you give mice vitamin D, it reduces tumor growth by as much as 40 percent to 50 percent
What bothers me about your research is the inflated claims you make for it. You say that one pill can prevent and treat everything from cancer to autism to depression. There has never been a medication that did all that.
I never said autism.
It’s on the cover of your book!
O.K. There has been an association between vitamin D deficiency and autism. More studies need to be done. What I recommend certainly is that autistic children receive vitamin D, because it improves muscle function.
Do any vegetables contain vitamin D?
It turns out, curiously, that mushrooms contain vitamin D. Then, of course, there are the fortified foods, which are principally the dairy products with 100 units of vitamin D per serving.
Which is why our mothers made us finish our milk. It sounds as if it is almost impossible to get enough D in one’s daily diet through food alone.
The bottom line is that everybody should be taking a supplement. I do it, even though I’m out there cycling for an hour or two without sunscreen on my arms and legs.
In that case, you should be checked for melanoma. Do you have a dermatologist?
No. I don’t have wrinkles. I do a skin survey on myself every couple of months just looking in a mirror. INTERVIEW HAS BEEN CONDENSED AND EDITED.
Two bodies, in fact. The first concerns the emerging science of epigenetics, the study of how the environment modifies the way genes are expressed. Since the days of Crick and Watson, we’ve tended to see genes as a set of straightforward instructions, a blueprint for constructing a person. Over the last 20 years, however, some scientists have begun to complicate that picture. “It turns out that the genetic instructions themselves are influenced by other inputs,” Shenk writes.
“Genes are constantly activated and deactivated by environmental stimuli, nutrition, hormones, nerve impulses and other genes.” That means there can be no guaranteed genetic windfalls, or fixed genetic limits, bestowed at the moment of conception. Instead there is a continually unfolding interaction between our heredity and our world, a process that may be in some measure under our control.
The second body of research investigates the nature of exceptional ability and how it arises. We’ve traditionally regarded superior talent as a rare and mysterious gift bequeathed to a lucky few. In fact, Shenk writes, science is revealing it to be the product of highly concentrated effort. He describes the work of the psychologist Anders Ericsson, who wondered if he could train an ordinary person to perform extraordinary feats of memory.
When Eric sson began working with a young man identified as S.F., his subject could, like most of us, hold only seven numbers in his short-term memory. By the end of the study, S.F. could correctly recall an astonishing 80-plus digits. With the right kind of mental discipline, Ericsson and his co- investigator concluded, “there is seemingly no limit to memory performance.” Shenk weaves accounts of such laboratory experiments, conducted on average people, with the tales of singularly accomplished individuals — Ted Williams and Michael Jordan, Mozart and Beethoven — who all worked relentlessly to hone their skills. ... http://www.nytimes.com/2010/03/21/books/review/Paul-t.html