Among the most interesting vitamin D facts may be that vitamin D is not a vitamin at all, but a natural hormone. Vitamin D is made on your skin, goes into your bloodstream and then to your liver and kidneys to get activated, then goes to your intestines and bones to do its biological work. This process indicates that vitamin D is, by definition, a hormone.
Since vitamin D is a hormone that works throughout the body, it affects every facet of your health. Some of the more commonly-known health benefits of vitamin D include:
Vitamin D for cancer prevention. Worldwide cancer rates have a direct correlation with the amount of sun exposure people get. Populations that live away from the equator have much higher rates of many common cancers, including cancer of the colon, prostate, breast and ovaries. This is consistent even across different cultures and economic levels all around the world.
Get more details at Health Benefits of Vitamin D
Sun exposure has always been man's primary source of vitamin D. Vitamin D is produced by your skin from exposure to ultraviolet radiation from sunlight. Just 30 minutes summer sun exposure in a bathing suit (without sunscreen) produces at least 10,000IU vitamin D.
repeated warnings about the danger of skin cancer has made much of the
public avoid sun exposure altogether. This is the primary cause of the
epidemic of vitamin D deficiencies we see today. In addition, you can't get any vitamin D from the sun during the winter months unless you live very near the equator.
More on this at Vitamin D From Sun Exposure
If you live north of 30 degrees north latitude (this includes most of the United States and all of Europe), you can only get adequate vitamin D from sunlight for about six months out of the year — from April through September, in most regions.
Sunscreens — even the weakest ones (SPF 8) — block your body’s ability to generate vitamin D by 95%.
People with dark skin pigmentation have built-in sun protection that’s similar to a sunscreen with a SPF of 15-30. They need much more sun exposure to get adequate amounts of vitamin D.
Obese? Overweight individuals may be less able to manufacture Vitamin D, and, consequently, need more exposure to sunlight.
More on this topic at Causes of Vitamin D Deficiency
It is nearly impossible to get adequate amounts of vitamin D from your diet. You would have to drink ten glasses of vitamin D-fortified milk or orange juice each day just to get 1000IU of vitamin D from your diet. Very few other foods have any vitamin D at all.
The food highest in natural vitamin D content is salmon. It has approximately 400IU in a 4oz. serving, much less than your daily requirement.
More on this at Foods That Contain Vitamin D
Vitamin D deficiency has been associated with a long list of chronic illnesses that could also have any number of other underlying causes. This makes it very difficult to diagnose. Here is a list of many of them:
Important things to know about vitamin D deficiencies:
There are usually no symptoms of vitamin D deficiency until you have a serious chronic illness, something that is extremely difficult to trace back to its cause.
Chronic vitamin D deficiency is often misdiagnosed as fibromyalgia because its symptoms are so similar: muscle weakness, aches and pains.
Chronic vitamin D deficiency cannot be reversed overnight. It takes months of vitamin D supplementation and sunlight exposure to rebuild the body’s bones and nervous system.
More on this at Symptoms of Vitamin D Deficiency
A number of recent studies have shown that vitamin D deficiencies are at epidemic levels. The current recommendation for minimum blood levels of vitamin D is 50 ng/ml (nanograms per milliliter)
The Life Extension Foundation analyzed results from 13,892 blood tests in members who had their blood levels of vitamin D evaluated from March 2008 to September 2009.
Their findings looked like this:
• 38% of test results for vitamin D were less than 30 ng/ml (the previous minimum threshold).
• 69% of test results were less than or equal to 40 ng/ml, and
• 85% of test results were less than or equal to 50 ng/ml, now recognized as a minimum level for optimal health.
The Whitaker Wellness Center, the largest alternative medical clinic in America, tests nearly every patient for their vitamin D levels when they are admitted. And guess what they find? Roughly 95% of new patients have deficient vitamin D levels.
Vitamin D Facts: Most hospitals in America — and most doctors practicing medicine — don't even test for vitamin D levels. Why not? Because doctors are so absorbed with other therapies such as drugs and surgery that they have completely overlooked the simplest and most powerful tool for health and healing: nutrition.
Learn more about this at Symptoms of Vitamin D Deficiency
How do you know if you have a low vitamin D level? If you don't spend
much time in the sun, live someplace away from the equator and don't
take any vitamin D supplements, you are almost certainly vitamin D
deficient. Most everyone suffers from low levels during the winter months.
The only sure way to determine if you have a normal vitamin D level is to get your blood levels tested. You can arrange this with your health care provider, or order an inexpensive home blood test.
See my page on Vitamin D Blood Test for more information.
For many years, the official recommended daily allowance for vitamin D had been set at 200-600IU per day. That now appears to be significantly too low to provide the greatest health benefits of vitamin D, such as good bone mineral density, dental health, fractures and cancer prevention. It's also nearly impossible to achieve these levels through diet alone, because very few foods contain any vitamin D.
Most recommendations for vitamin D now call for at least 2,000IU per day. 5,000IU per day is not unreasonable, especially if you get little or no sun exposure, live in northern latitudes, or are dark-skinned or overweight. Even more may be necessary if you're chronically deficient. Higher dosages are recommended during the winter months, when you aren't any vitamin D from the sun.
See my page on Vitamin D Dosage for more details.
Vitamin D toxicity seems to be a very common notion today, even among physicians. If you examine it closer, though, it's a theory based on very flimsy evidence and often misinterpreted observations taken from a handful of unusual cases.
Cholecalciferol/vitamin D is certainly toxic in excess. However, vitamin D toxicity is virtually unheard of until the dose exceeds 10,000IU per day. In adults, taking 50,000IU/day for more than a few months can produce toxicity. However, there would be no reason for anyone to do this, unless they are being treated for severe vitamin D deficiency by a health care provider.
See my page on Vitamin D Toxicity for more details.
Every recent study on vitamin D blood levels indicates that the majority of the population is deficient in vitamin D, whatever the reason. If you don't sunbath regularly and take vitamin D supplements in the winter, you almost certainly have low vitamin D levels in your bloodstream. Fortunately, vitamin D3 supplements are very inexpensive and safe to take.
For tips on buying and using vitamin D supplements, see my page on Vitamin D Dosage.
Visit other pages on this website for more vitamin D facts:
Other Great Resources for Vitamin D Information:
Grassroots Health A consortium committed to solving the worldwide vitamin D deficiency epidemic.
Dr. Mercola Lecture on the most up-to-date science on vitamin D.
How Much Vitamin D Do You Need? An article by Dr. Mercola.
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