(NaturalNews) Thanks to sun avoidance and indoor lifestyles, Americans are vitamin D deficient. One of the worst things Americans have done to their health is avoid sun exposure. Most of us work inside then sit in our cars, and when we're outside we slather ourselves with sun block and wear wide-brim hats and long sleeves. As a result, the majority of Americans have a serious vitamin D deficiency. It's important to know whether your vitamin D levels are low, because a deficiency can increase the risk of our most common diseases, including heart disease and cancer.
In addition to its role in enabling calcium to be absorbed from the gut, new research is showing that vitamin D prevents heart disease, and stops the out-of-control cell growth that characterizes cancer. A number of population studies are suggesting that the less sunshine we get, the higher our risk is for cancers of the colon, prostate, breast, lung and, believe it or not, skin. Other research shows that vitamin D deficiency may be causing autoimmune diseases such as fibromyalgia and multiple sclerosis (MS). Research published in the British Medical Journal
(vol. 237, p.316) on multiple sclerosis suggests that children who are exposed to the sun an average of two to three hours a day in the summer are a third less likely to develop MS. Vitamin D deficiency can also cause muscle weakness, osteoporosis and chronic low back pain.
The Sunshine Vitamin
Vitamin D is called the sunshine vitamin. When the sun's ultraviolet rays are absorbed by the skin, a biochemical process begins in which an active form of vitamin D
is created, enters the blood stream and then the cells. You can also get vitamin D from foods such as oily fish, dairy products and supplements, but sunshine is by far our most important source of this essential vitamin.
But haven't we been warned away from sun
exposure? Won't it cause cancer and wrinkles? Well, yes and no. Our national hysteria about sun damage is grossly exaggerated. It's one of those myths that has been repeated so much that most everyone assumes it to be true. The sunscreen industry has done a great job selling its wares by scaring us about sun exposure. However, if you dig down and do some research it's a different story.
Yes, if you repeatedly get sunburned you somewhat increase your risk of non-melanoma skin
cancer and wrinkles. The fairer the skin, the more easily it is sunburned and damaged. By far the biggest risk for skin cancer is simply having fair skin - with or without sunscreen. There's really no substantial evidence that using sunscreen protects you from skin cancer
. There is a weak association between melanoma and sunburn, but there is no evidence that using sunscreen prevents melanoma. There is some research indicating that exposure to the sun as a child reduces
the risk of melanoma.
How Much Sun Do We Need?
According to Michael Holick, a vitamin D researcher and author of the book, The UV Advantage
, between 11 a.m. and 2 p.m. in the summer (when the sun is most intense), a Caucasian with medium-fair skin living in Boston needs five to eight minutes of sunshine daily without sunblock
. In winter you need more sun. People who live further north and/or have darker skin need more time and conversely, people who live closer to the equator and have fairer skin need less time.
There is considerable controversy about whether the process of skin tanning is beneficial and protective against the sun's harmful rays, or whether tanning is actually a symptom of skin damage. Although repeated sunburns are correlated with later skin cancers, people who are brown from spending their lives working outside in the sun do not have higher rates of skin cancer: factors such as light skin, freckles, numerous moles, genetics and exposure to radiation and arsenic are greater risk factors.
The bottom line on healthy sunning is to avoid sunburn; in fact, you should be out of the sun long before your skin starts turning red. If you're pale as a ghost, begin with just a few minutes a day and gradually work up. If you're worried about facial wrinkles, wear a hat to shield your face, but allow at least your arms, legs and some of your chest to be exposed.
For those who have low vitamin D levels, live in colder, cloudier, northern climates or who just can't get out in the sun enough, it's wise to take a vitamin D supplement. The recommended daily allowance (RDA) of 400 IU is clearly too low. It was put in place before Americans became sun-phobic. Vitamin D is a fat soluble vitamin and as such can accumulate in the body and become toxic, so there has been justifiable concern about taking too much. Now that we have more research, it seems clear that we can safely take 2,000 IU daily in the D3 cholecalciferol form to maintain our vitamin D levels. If you are seriously deficient and your doctor wants to ratchet up your vitamin D levels quickly with large doses, be sure to test levels regularly. Some doctors will recommend 10,000 IU for a few months to get vitamin D levels back to normal.
What Is an Optimal Vitamin D Level?
Vitamin D levels below 20 ng/mL indicate a deficiency, while levels below 30 ng/mL are considered "low." At this time, the scientific consensus is that optimal vitamin D levels are 30 to 60 ng/mL. Vitamin D can become toxic at levels greater than 150 ng/mL, which is why it's important to test if you're taking high dose supplements.
Who Is at Risk for Deficiency?
* The Elderly:
As we age we absorb less vitamin D from the sun's UV rays. Living in a nursing home or becoming homebound can limit exposure to sunshine. Muscle weakness and osteoporosis associated with vitamin D deficiency make the elderly more susceptible to falling and to fracture risk. Research indicates that vitamin D supplementation may decrease the risk of fractures.
* People with Dark Skin:
The darker the skin is, the higher melanin levels are. Melanin blocks the action of sunlight on vitamin D precursors in the skin, requiring much longer sunlight exposure to generate adequate circulating vitamin D compared to people with fair skin.
* People with Limited Sunlight Exposure:
People living at northern latitudes or who have limited sunlight exposure because of their working environment or cultural dress rules may have low vitamin D levels.
* People with Musculoskeletal Pain:
People with symptoms of hypothyroidism, non-specific musculoskeletal pain, chronic low back pain, or fibromyalgia are frequently found to have low vitamin D levels and show clinical improvement after supplementation.
* Overweight or Obese People:
Vitamin D can be locked up in fat stores in people who are overweight or obese. In clinical studies, obesity is associated with lower levels of circulating 25-hydroxy vitamin D.
New, Simple Vitamin D Test You Can Do at Home
Until recently, testing vitamin D levels involved a visit to the doctor, then a visit to a lab to draw blood, and considerable expense often not covered by health insurance. Thankfully there's now a reasonably priced and simple-to-use blood spot test available to consumers that can be done at home.
What Is a Blood Spot Test?
A blood spot test involves a nearly painless finger stick and putting a few drops of blood on a small piece of special blotting paper.
Is the Blood Spot Test for Vitamin D Accurate?
It is highly accurate and unlike others, gives you a measure of both vitamin D2 and D3 and easy-to-interpret results.
To read more about vitamin D, find more references, and order a blood spot test, please visit the Virginia Hopkins Test Kits website (http://www.virginiahopkinstestkits.com/vitamindtest.html) .
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Grant WB, "An estimate of premature cancer mortality in the U.S. due to inadequate doses of solar ultraviolet-B radiation," Cancer 2002; 94:1867–75.
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Lin J, Manson JE et al, "Intakes of calcium and vitamin D and breast cancer risk in women," Arch Intern Med 2007 May 28;167(10):1050-9.
Robien K, Cutler GJ et al, "Vitamin D intake and breast cancer risk in postmenopausal women: the Iowa Women's Health Study," Cancer Causes Control 2007 Sep;18(7):775-82.
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About the author
Virginia Hopkins is a best-selling author and co-author of books about women's hormones, nutrition, prescription drugs and more, including What Your Dr. May Not Tell You About Menopause with Dr. John Lee, and Prescription Alternatives.
Virginia is currently editor of the Virginia Hopkins Health Watch newsletter, at http://www.virginiahopkinstestkits.com/hopkinshealth.html