Study shows more benefits of sunshine vitamin

LONDON (Reuters) - People with a vitamin D deficiency are as much as twice as likely to die compared to people whose blood contains higher amounts of the so-called sunshine vitamin, Austrian researchers said on Monday.

Their study -- the latest to suggest a health benefit from the vitamin -- showed death rates from any cause as well as from heart-related problems varied greatly depending on vitamin D.

"This is the first association study that shows vitamin D affects mortality regardless of the reason for death," said Harald Dobnig, an internist and endocrinologist at the University of Graz in Austria who led the study.

The body makes vitamin D when the skin is exposed to sunlight, a reason for its nickname as the "sunshine vitamin." It is added to milk and fatty fish like salmon but many people do not get enough of it.

Vitamin D helps the body absorb calcium and is considered important for bone health. In adults, vitamin D deficiency can lead to osteoporosis, and it can lead to rickets in children.

A number of recent studies have also indicated vitamin D may offer a variety of other health benefits, including protecting against cancer, peripheral artery disease and tuberculosis.

Last week, U.S. researchers said vitamin D may extend the lives of people with colon and rectal cancer.

Dobnig and colleagues, who reported their findings in the Archives of Internal Medicine, studied more than 3,200 people with an average age of 62 who were scheduled for a heart exam between 1997 and 2000.

During an eight-year follow-up the researchers found that the quarter of volunteers with the lowest levels of vitamin D in their blood were at greater risk of dying.

Even when accounting for factors such as heart disease, exercise and other conditions, the researchers found that the risk was double for people with between 5 to 10 nanograms per millilitre of vitamin D in their blood, Dobnig said.

Most doctors believe people should have between 20 to 30 nanograms per millilitre of the vitamin in their blood, he added in a telephone interview.

What causes this effect is not clear, but Dobnig pointed to a host of studies suggesting links to high blood pressure, cancer and fractures as places to begin looking.

The potential health risk of low levels of vitamin D should also prod physicians to be more aware of the potential problem, especially for the immobile, elderly and others who spend a great amount of time indoors, he added.

Many doctors agree that people with low levels of vitamin D cannot make up for it safely by sitting in the sun, but should take supplements.

"These results should prompt us to perform vitamin D measurements on a more frequent basis especially in populations at risk," Dobnig said.

(Reporting by Michael Kahn; Editing by Maggie Fox)

Vitamin D Deficit May Boost Men's Heart Attack Risk

Men who have low levels of vitamin D, which comes from sunshine and fortified milk, may be at risk for having a heart attack, researchers said.

Heart disease is the leading cause of death in the industrialized world, and kills 869,000 people in the U.S. each year, according to the American Heart Association. Deaths from heart disease rise in the winter, at higher latitudes and lower latitudes, where exposure to sun declines, the researchers said.

They tracked the health history of 18,225 men in the Health Professionals Follow-Up Study, comparing those who had a heart attack or died from heart disease with healthy participants. Men with a vitamin D deficiency at the start of the study were more than twice as likely to have a heart attack as those in the normal range, even after other reasons such as family history, weight, diabetes and cholesterol levels were considered.

``The risk of dying of a heart attack was even higher,'' said Edward Giovannucci, the lead researcher and professor of nutrition and epidemiology at the Harvard School of Public Health in Boston, in a telephone interview. ``Particularly for people who live in the northern-most states and in the winter months, when we don't get a lot of exposure to sunlight, 1,000 to 1,500 units a day of Vitamin D may be warranted.''

The study, funded by the National Heart, Lung and Blood Institute and the National Cancer Institute, appears in today's Archives of Internal Medicine. Previous studies found women who don't get enough sunlight may be at greater risk from aggressive breast cancer.

Sunny Days

Sunshine is the greatest source of vitamin D, produced when ultraviolet light strikes the skin. Studies have shown vitamin D, which occurs naturally in few foods, may make several types of cancer less lethal and protect against breast cancer, the most common malignancy in women.

On a sunny day in the summer, just 10 minutes outside in shorts and a T-shirt will generate enough vitamin D to reach the higher levels found protective in the study, Giovannucci said. Light-skinned people, the group with the highest risk of skin cancer, are the most efficient at producing vitamin D and need the least time in the sun, he said. Darker-skinned people need two to three times longer, he said.

``The people most concerned about skin cancer should definitely not be baking in the sun, but for about 10 minutes at midday, you can make a lot of vitamin D quickly,'' he said. ``You don't need to get a sunburn to make vitamin D.''

Sunscreen

Sunscreen partially blocks vitamin D production, particularly when lotions with higher sun protection factor, or SPF, levels are used. Some vitamin D is produced even when sunscreen is applied thoroughly, something most people don't do, according to the National Institutes of Health Office of Dietary Supplements.

In the winter, spending an entire day outside might not yield much vitamin D, Giovannucci said. And it may take 10 to 15 glasses of milk to raise men from the lowest levels to the highest, he said. It is during those winter months that supplements may be helpful, he said.

The reason for the protective effect of vitamin D isn't clear, though there are several hypotheses, he said.

Vitamin D can help lower blood pressure and reduce calcium deposits in the arteries, the fatty plaque that can rupture to cause clots and heart attacks, he said. It may also help reduce the risk of respiratory ailments that can be tied to heart attacks or help the heart muscle function better, he said.

To contact the reporter on this story: Michelle Fay Cortez in Minneapolis at mcortez@bloomberg.net

Fighting Breast Cancer? Take Your Vitamin D

Researchers have found that breast cancer patients who don't have enough vitamin D in their bodies are much more likely to have their cancer spread and to die from the disease.

For millions of women, the finding in a new study raises the possibility that a basic nutrient like vitamin D, a vitamin pill that costs just pennies a day, might have a profound impact on their breast cancer.

Click here to watch the video.

Dr. Anne McTiernan at the Fred Hutchinson Cancer Research Center said, "This study is significant because it tells us this may be one thing women can do to improve their prognosis."

Researchers, following more than 500 women with breast cancer, found that women deficient in vitamin D were 94 percent more likely to have their cancer spread and 73 percent more likely to die from their cancer.

JoEllen Welsh, a professor at the State University of New York at Albany, said, "Vitamin D is pretty unique in its action in that it does enter the cancer cells and induces them to undergo a cell death process."

Welsh should know. She studies vitamin D in her laboratory. Under a microscope, she showed ABC News a cluster of human breast cancer cells that shriveled up and died when she added vitamin D.

"The effects of vitamin D on breast cancer cells are very similar to the established drug Tamoxifen that many women take for breast cancer."

Vitamin D, essential for strong bones, has also been linked in several studies with cancer prevention. And not only breast cancer but colon and prostate cancers as well.

The problem, said cancer researchers, is that many women and men are not getting enough vitamin D. In this latest study, 76 percent of the breast cancer patients had low levels of the nutrient.

A simple blood test can determine whether someone is vitamin D deficient and by how much.

McTiernan, a researcher in breast cancer prevention, exercises daily, eats nutritiously and recently discovered that she too had dangerously low levels of the nutrient.

"I was very surprised at how low my vitamin D levels were. I thought I was doing everything right." she said.

Now with daily vitamin D supplements, she just might be.

For more information on vitamin D, check out the fact sheet provided by the National Institues of Health here.

Copyright © 2008 ABC News Internet Ventures

Are babies hurt by lack of vitamin D?

Vitamin D deficiency is quite common in babies, and breast-fed infants appear to be at greater risk than bottle-fed ones, according to a new study.

Researchers found "suboptimal" levels of the bone-building vitamin in 40 percent of 380 otherwise healthy infants and toddlers tested at Children's Hospital Boston, with 12 percent considered to be clinically deficient. Breast-fed infants were up to 10 times more likely to be deficient in vitamin D than their bottle-fed counterparts, according to the study in the June issue of the Archives of Pediatrics and Adolescent Medicine.

In addition to helping build strong bones, vitamin D - which the body synthesizes from sunlight - may play a key role in reducing the risk of diabetes, multiple sclerosis, and some cancers. The fat-soluble vitamin is generally present in foods only in small quantities, so in the United States, it's added to milk, multivitamins, and some cereals and juices.

Rates of vitamin D deficiencies are on the rise in both children and adults, research shows, as we slather on sunscreen and spend more time indoors.

But the new study's findings go straight to the heart of an ongoing debate in medicine - how much vitamin D do we really need, and what's the best way to get it?

In a cautionary editorial accompanying the study, University of Washington pediatrics professor Dr. James A. Taylor noted a lack of consensus among medical experts about what constitutes the best level of vitamin D for health. There is little research showing any long-term effects from early vitamin D deficiency in children, Taylor said, although he acknowledged that such research would be difficult to conduct.

"It seems like we're medicalizing people that we don't need to medicalize," Taylor said. "The question is whether these children have any long-term health risks, and I don't think we know that."

The new study involved a largely African-American and Latino group of children, aged 8 to 24 months, who visited a clinic at Children's Hospital between 2005 and 2007.

Dark-skinned children and adults are at particular risk of deficiency, because the extra pigmentation in their skin interferes with the body's ability to produce the vitamin. Vitamin D levels also have been shown to decline in winter months.

Only 20 of the children were exclusively breast-fed, and of those, only six received a vitamin D supplement. The researchers performed X-rays on the children whose blood tests showed a vitamin D deficiency and found that nearly a third showed evidence of the weakening that can lead to rickets, a softening of the bones that can trigger fractures and deformities. One child even showed physical signs of the disease. The vitamin D-deficient children were offered enrollment in a treatment trial.

One of the study's most surprising conclusions is that the primary risk factor for vitamin D deficiency was breastfeeding without supplementation, rather than children's skin color or the time of year, said lead author Dr. Catherine Gordon, director of the Bone Health Program at Children's Hospital.

"A tenfold increase in risk is huge. It's a startling difference" Gordon said, although she acknowledged that the actual number of exclusively breast-fed children was small.

Mothers who breastfeed are often vitamin D-deficient, so the American Academy of Pediatrics since 2003 has recommended supplementing the diets of exclusively breast-fed babies with 200 units a day of vitamin D, particularly if they live in northern climes. Baby formula typically is fortified with vitamin D.

The finding could rile breastfeeding advocates, who fear that recommending supplementation of any kind might scare some women away from the practice, which studies show has other health benefits. Gordon was careful to note that she wholeheartedly supports breastfeeding but recommends vitamin D supplementation.

Noted vitamin D expert Dr. Michael Holick of the Boston University School of Medicine, who praised the study, believes that the American Academy of Pediatrics recommendations for supplementing breast-fed infants is inadequate and that all children require vitamin D supplements and moderate sun exposure for optimal health.

"Vitamin D deficiency is one of the most common medical conditions nationwide," said Holick, who has come under criticism for accepting funding from the tanning industry.

Dermatologists caution that sun exposure can increase the risk of skin cancer.

Source: Boston.com