Sunlight—Required Nutrient, Not a Health Risk

by Heidi Stevenson

22 June 2009

There's one supplement, above all others, that the vast majority of people need more than they're getting: Vitamin D3. This fact has been getting plastered all over the media, but just what it means and how one should resolve the problem is a bit hazy. Part of the reason is simply misinformation, but that's not the whole story. The Vitamin D3 issue is not fully understood by anyone, other than the fact that a significant amount of ill health is related to a deficiency of it.

Throughout most of humanity's history, lack of D3 was exceedingly rare. Most people spent most of their time outdoors, getting plenty of sunlight. Now though, most of us spend most of our time inside. Worse, we're told to either stay out of the sun, as if it's an enemy, or to slather our skin with toxic creams and lotions.

It has been clearly documented, though, that calciferol is an important nutrient and that the way our bodies synthesize it is with sunlight—in fact, before the supplements of modern times, it was the only feasible way to obtain adequate quantities of D3. Our skin makes D3 with one part of sunlight's spectrum, ultraviolet B light. It converts a form of cholesterol, oxycholesterol, into calciferol.

Below the Ad: Conditions Associated with Inadequate D3

Conditions Associated With Inadequate D3

Here's a video with Dr. Cannell, who is likely the foremost researcher on Vitamin D. He discusses how extensive is D3's effects on the body and how severely its lack impacts on health.

An enormous range of chronic conditions are related to a shortage of cholecalciferol. Here's a partial list:

D3 is required by virtually every cell in your body.
• Parkinson's Disease
• Multiple Sclerosis
• Cancer
• Heart and Circulatory Disease
• Alzheimer's Disease
• Diabetes
• Osteoporosis
• Tuberculosis
• Kidney Disease
• Hepatitis C and Cirrhosis
• Ulcerative Colitis and Crohn's Disease
• Thyroid Disorders
• Rheumatoid Arthritis
• Rickets, the classic Vitamin D deficiency disorder

The range of disorders associated with lack of D3 is mindboggling, and this points to the fact that D3 is required by virtually every cell in your body. It is a prehormone, the most potent found in the human body. Note that multiple sclerosis is almost unknown at the equator and becomes more common with distance towards the north. Though not proof—and there most assuredly are other problems likely tied to it—there does seem to be a connection between the time when people started to move indoors for work and the increase in chronic diseases.

What About Skin Cancer?

It is true that sun exposure has been linked to melanoma, a particularly virulent form of skin cancer. This is why we've been told to stay out of the sun and use sunscreens. Tanning, though, is not the problem. Burning is. A history of sun exposure is not a predictor of melanoma risk. What matters is a history of sunburn. So, people who've had sunburns, especially severe ones, need to be aware that they are at increased risk of melanoma.

However, even if you've had sunburns, that is not a reason to avoid the sun now. It is, in fact, a good reason to make a point of getting in the sun. Paradoxically, even the risk of melanoma is increased by inadequate D3!

How Much Sunlight Do We Need?

This is the big question, and the fact is that there's no simple answer. It has not been quantified exactly how much Vitamin D is needed or how much sun exposure would be required to got it, even if we did know. It is, though, possible to identify whether we're getting enough Vitamin D.

The problem with determining appropriate sun exposure is related to a variety of factors, such as how far removed we are from the equator, weather, pollution, season, altitude, age, clothing, and skin type. The more clothes worn, the less skin surface that's exposed to sunlight, so less D3 is made. Darker skinned people can take far more sun exposure than those with light skin. That protection from burning, though, comes at a cost. Dark skin is resistant to making cholecalciferol, so more sun is required. The sun's rays go through more atmosphere during winter than summer, so have less effect in the winter. Clouds filter out some of the ultraviolet B light, which are the tanning and D3-making rays, but not the ultraviolet A rays, which are the ones that burn. Pollution can interfere with the sun's intensity, and at higher altitudes, the sun's rays are stronger. All these factors make knowing how much sun is needed a difficult task. Add to that how much skin is exposed, and the problem is even worse.

There are suggestions—mostly from the allopathic world, which is still generally concerned about melanoma—that it takes very little sunlight to obtain adequate D3. However, the truth is that it's very difficult to quantify and claims of how much is needed are generally based on nothing but guesswork.

How Do We Know If We've Gotten Enough D3?

Fortunately, it's quite easy to determine whether we have enough D3. A simple blood test can identify how much is in our systems. Simply ask your doctor for a blood test to check on cholecalciferol levels. Be sure to get the actual results, not just your doctor's opinion, since most doctors are not up to par on this subject.

There are some differing views on what an adequate blood level of D3 is. However, it's clear that levels considered good enough only a few months ago are now clearly inadequate. It has been demonstrated that anything below 32 ng/ml (nanograms per milliliter) is dangerously deficient. What now appears to be optimal is 50-64 ng/ml⁽¹⁾, and excessive would be greater than 100 ng/ml—though dangerous levels cannot be reached when D3 is created through sunlight exposure.

Unfortunately, lab tests for Vitamin D3 are not consistent, so you need to know type of test is being used. In the US, the best test is the radioimmunoassay (RIA) produced by DiaSorin, though the reason isn't its superiority, but that it's the one that's been used to establish adequate and optimal amounts of blood cholecalciferol. It's difficult to know if your results are high or low when the test is based on a different measurement.

Two other test types are in fairly common use. The liquid chromotatography-mass spectrometry (LC-MS/MS) test is used by many important labs, including the Mayo Clinic. The Liaison test is a relatively new assay that is rapidly replacing the original RIA test. It also is done by DiaSorin.

You need to assure that the reported results have been calibrated against DiaSorin's RIA results. Otherwise, it's possible that they will be off by a significant amount. It's possible that they'll be as much as 40% off—an amount that could indicate optimal Vitamin D levels, when you're actually deficient.

Note: Another way to specify the correct test is "25(OH)D" or "25-hydroxyvitamin D".

The Importance of Not Overdoing Your Sunning

Now that you're aware of the importance of getting adequate D3 and how to have it tested, let's go back to the issue of too much sun. Don't ever forget that sunburns are harmful. They are a strong predictor of getting one of the most aggressive forms of cancer, melanoma. There is another reason, too.

You may be thinking that it's worth the risk of getting burned, with the idea that the benefits of D3 outweigh the risks. That is not the case. Please, be sure that you avoid burning. Be aware that many people do not show signs of burning until several hours later. It's very important to be cautious initially to assure that you don't overdo it. Take it slowly at first, especially if your skin is very light.

There's a good deal more to this subject of D3 and how to obtain it. While the natural approach, getting it from the sun, is certainly best, How to Get Vitamin D Without the Sun addresses other methods, including foods, suntan booths, and other factors in obtaining optimal cholecalciferol for your health.

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