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The Overwhelming Evidence That Sunlight Fights Cancer

sun, sunlight, vitamin DA new paper analyzes the case for vitamin D’s cancer-fighting power by looking at the well-known Hill criteria for examining causality in a biological system. The Hill criteria look at:

1. Strength of association
2. Consistency (repeated observation)
3. Specificity (one agent, one result)
4. Temporality (exposure precedes effect)
5. Biological gradient (dose-response relation)

6. Plausibility (e.g., mechanisms)
7. Coherency (no serious conflict with the generally known facts of the natural history and biology of the disease)
8. Experimental verification (randomized, controlled trial)
9. Analogy with other causal relationships

The theory that solar ultraviolet radiation -- and by extension, vitamin D, which is produced when such radiation strikes your skin -- is a potent cancer fighter satisfies most, if not all, of the criteria. From a scientific point of view, therefore, vitamin D reduces the risk of many forms of cancer and increases survival rates once cancer reaches a detectable stage.

However, public policy often lags behind scientific research. It is to be hoped that the acceptance of the beneficial nature of vitamin D in reducing the risk of cancer and many other diseases will not have too much longer to wait. It is encouraging that the National Academy of Sciences’ Institute of Medicine is currently embarking on a two-year study of vitamin D, and is expected to issue a report in 2010.

Sources:

Dr. Mercola''s Comments Dr. Mercola's Comments:

In the last few years the evidence has been pouring in that sunlight fights cancer by producing vitamin D in your skin. Yet, public health officials have been shuffling their feet when it comes to putting the evidence into action.

This paper by Dr. William Grant, Ph.D., internationally recognized research scientist and vitamin D expert, shows just how strong the evidence that sunlight fights cancer really is.

In it he has applied the criteria for causality, originally suggested by Robert Koch to show that tuberculosis was caused by a bacterium and further organized in recent times by A. Bradford Hill.

This approach was used to evaluate whether the association between sunlight and decreased cancer rates can be considered causal, and after he applied the evidence, he found that the theory satisfied most, if not all, of the Hill criteria (the nine-step system listed above). There have also been numerous studies that speak to the power of sunlight in reducing your risk of cancer.

Sunlight: Nature’s Most Potent Cancer Fighter?

If health officials would simply recommend that you get some sensible sun exposure, or supplement with oral vitamin D3 if you can’t get out into the sun, there could be major advances made in the fight against cancer.

In short, your risk of cancer could be cut in half. This is according to a large-scale, randomized, placebo-controlled study that looked at almost 1,200 women, aged 55 and older, over the course of four years.

Those in a group that was given supplemental calcium and vitamin D had a 60 percent lower risk for all cancers than those who received a placebo.

Other research conducted by Dr. Grant found that about 30 percent of cancer deaths -- which amounts to 2 million worldwide and 200,000 in the United States -- could be prevented each year with higher levels of vitamin D.

Vitamin D has a protective effect against cancer in several ways, including:

• Increasing the self-destruction of mutated cells (which, if allowed to replicate, could lead to cancer)
• Reducing the spread and reproduction of cancer cells
• Causing cells to become differentiated (cancer cells often lack differentiation)
• Reducing the growth of new blood vessels from pre-existing ones, which is a step in the transition of dormant tumors turning cancerous

And for those who already have cancer, I believe it is virtually criminal malpractice, or at least gross medical negligence, to not optimize vitamin D levels when treating someone with this disease. As Dr. Grant wrote in his article:

“From a scientific point of view, vitamin D reduces the risk of developing many types of cancer and increases survival once cancer reaches the detectable stage.”

You Don’t Have to Wait for a Change in Health Policy

Making sure that your vitamin D levels are optimized is one of the simplest, yet most profound, things you can do to protect your health. It will likely be many decades before health policy catches up to what the evidence has already revealed, and widespread recommendations for increased sunlight exposure and vitamin D levels become the norm.

But you don’t have to wait, as you can optimize your levels right now.

The ideal way to optimize your vitamin D level is by exposing your skin to appropriate amounts of sunlight on large areas of your skin. Unfortunately for most of us there simply isn’t enough sun exposure for nearly half of the year. However, even when the sun is shining many of us are modern-day cavemen and spend the majority of the day inside at work or in our home. Not many of us are regularly out in the sun.

You typically need enough exposure to turn your skin the lightest shade of pink. If you have enough skin exposed you will produce about 20,000 units of vitamin D. Exposures any longer than turning your skin the lightest pink will not produce any additional vitamin D and potentially lead to premature skin aging and increase your risk of skin cancers.

Most of us struggle with vitamin D winters in which we may not be able to get enough sun exposure during certain parts of the year. In that case, I also advise using a safe tanning bed (one that has the harmful emissions shielded) to have your own body produce vitamin D naturally.

A third option is taking a high-quality vitamin D supplement. The most important thing to keep in mind if you opt for oral supplementation is that you only want to supplement with natural vitamin D3 (cholecalciferol), which is human vitamin D. Do NOT use the synthetic and highly inferior vitamin D2.

For those in the winter with no or very limited exposure to sunshine, 4,000-5,000 units per day is appropriate for most adults. If you are very heavy you may need to double that dose, and for children the dose can be half that.

When supplementing, make sure you have your levels monitored to make sure your levels are in the therapeutic range. For an in-depth explanation of what you MUST know before you get tested, please read my updated article Test Values and Treatment for Vitamin D Deficiency. If you live in the U.S. please be sure and use Lab Corp. Quest labs is not as accurate and you will likely need to multiply your results by 0.6 to give you a more accurate measurement of your true vitamin D levels.

One of the Most Important Videos You Will Ever Watch

If you are under the impression that your vitamin D levels are probably fine as they are, I have to warn you that vitamin D deficiency is pandemic in the United States. In fact, the late winter average vitamin D in the U.S. is only about 15-18 ng/ml, which is considered a very serious deficiency state. Meanwhile, it’s thought that over 95 percent of U.S. senior citizens may be deficient, along with 85 percent of the American public.

Making sure that you implement the simple steps necessary to optimize your vitamin D levels is therefore of crucial importance for your own, and your family’s, health. This is why I recorded a one-hour video lecture about vitamin D -- so you can learn the nearly unbelievable benefits you will receive by understanding this vital nutrient.

Please set aside one hour to watch the video, as it is easily one of the most important messages you will hear this year.


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Comment on This Article Community Comments (28)
 
 
Posted On Jan 20, 2009

I have this nagging feeling that we are still in the dark.  Vitamin D was, I believe, characterized in 1928;  a Nobel Prize was awarded.  But from then until now we have known virtually only one good thing about it; below a particular serum level leads to bone disease.  Science has a major problem in frequently jumping to conclusions, why? I don't know but as a scientist I see it all the time.  In this case it was assumed for nearly a century, on the basis of not having looked that vitamin D was good for nothing else.  Its a wonder scientists haven't become extinct from crossing roads, assuming the one car to go by is the only one, then to step out and to be run over by a truck.

Is this not happening again? now we've found the association between the levels of D and cancer and are now assuming this is all there is.  The anecdotal clues about the eyes should tell us there is more.  Can anyone point to data showing that the only necessary thing the sun does when it shines on the body is produce vitamin D at a level necessary to inhibit cancer?  If not why are we assuming that?  Are there other diseases that are inhibited by adequate levels of other things induced by sun exposure yet to be discovered?  Until I see a more competent attitude to scientific study I'm going to continue to get lots of sun, without burning of course.  After a number of years of following basic health science research and discovery I believe the score in "First to Discover" now stands at Old Wives 47 : Science 19.  Dr. Mercola and others on the internet deserve the  credit for the breakout.


 
Track Record
Novice User Novice User, Joined On 1/2009
Track Record  
Replied

Dr. Mercola
Master User Master User Joined On 12/1997
Dr. Mercola  
 
Posted On Jan 20, 2009

Good points. That is why I recommend the sun or a safe tanning bed and NOT oral vitamin D. If one can't afford the UVB exposure then oral vitamin D is clearly better than not supplementing.

The reason vitamin D knowledge has exploded in the last ten years, is the ability to inexpensively and accurately test it. This test only became available in the late 90s and it takes a number of years to write grants and get funding to do the necessary research to document the actions of vitamin D.

I suspect we will also see an explosion of information about vitamin A once we get a similar test as currently there is no inexpensive commercial assay for vitamin A.


 
 
 
Posted On Jan 20, 2009

As a natural health author and researcher, and a follower of Doctor Mercola and the Vitamin D Council, I continue to be more impressed by all the information about the vital roles of sunshine and Vitamin D3, as well as the health benefits of indirect sunlight.

To quote from my own natural anti-cancer protocol (www.tbyil.com/anticancer.htm):

"From the very first days that man walked upon the earth, sunshine has been a key to health and survival.  The importance of the synergistic relationship between health and regular sunshine cannot be over-emphasized for both physical healing and mental health (which is itself a key to physical healing for cancer and any other illness).  Contrary to popular beliefs about the harmful effects of over exposure to the sun, abundant sunlight has extremely high success rates for:

Safely stopping tumor growth

Preventing cancer by stimulating the body's vitamin D production.

Preventing influenza

. . . sunshine is essential to the production of vitamin D, and, strange as it may sound, has been found to be essential in warding off melanoma as well as other cancers.  Be sure to get full body sun exposure avoiding the heat of the day and not allowing oneself to become more than mildly "pink" or sunburned by gradually increasing exposure time from a few minutes to perhaps a full hour and more each day.

Fair skin and the number of moles are the major risk factor for melanoma (skin cancer), not sunlight overexposure.

In 1959. Jane C Wright, directing cancer research at Bellevue Memorial Medical Center in New York City, instructed fifteen cancer patients to stay outdoors as much as possible that summer in natural sunlight without wearing their glasses, and particularly without sunglasses. By that Autumn, the tumors in 14 of 15 had not grown, and some patients had gotten better. It was discovered that the one patient that didn’t have good results . . . had continued to wear her prescription glasses."


 
Dquixote1217
Apprentice User Apprentice User, Joined On 4/2007
Dquixote1217  
 
 
 
Posted On Jan 20, 2009

What about those of us who have fair skin, family history of melanoma, blistering sunburns as kids and atypical moles?  Dr. Mercola stated in a previous article that a tan is one's skin's protection but I don't tan, just burn!  I really don't know what advice to follow at this point......advice welcomed.


 
pigwidgeon
Novice User Novice User, Joined On 1/2009
pigwidgeon  
Replied

ChrisH
Novice User Novice User Joined On 9/2006
ChrisH  
 
Posted On Jan 20, 2009

The amount of sun each person needs is drastically different, depending mostly on your ancestry.  You probably don't need much more than 15 minutes a day... and remember consistency is important.  Start out with just a few minutes a day and slowly work up to 20 or so(try 1 or two minutes added per day).  You can also boost your tolerance by optimizing your nutrient intake.  I find when I'm juicing regularly (fresh vegetable) It takes longer out in the sun for me to burn.



Heather Marsh
Apprentice User Apprentice User Joined On 5/2008
Heather Marsh  
 
Posted On Jan 20, 2009

I develop very blotchy facial skin after exposure to sunlight.

However, after checking my vitamin and mineral intakes on my diet software I have begun to take 500mcg of folic acid daily - and I am actually tanning a little for the second time in my life!



Dr. Mercola
Master User Master User Joined On 12/1997
Dr. Mercola  
 
Posted On Jan 20, 2009

Appropriate sunlight is still necessary and will still DECREASE your risk of cancer as it will increase your vitamin D level.  This is WELL documented. However, fair skinned people like you just need far less sunlight.  Perhaps only a few minutes of day in the summer.  Anymore will increase your risk of cancer.

Appropriate means that your skin has turned the LIGHTEST pink possible on significant areas of your skin.. At that point your body will be producing 20,000 units of vitamin D.  Any further exposure that day will only cause skin damage.  Just be careful not to shower for the next 1-2 hours as the D needs to be absorbed into your bloodstream.  If you wash it off you will not get the vitamin D.



curious7
Savvy User Savvy User Joined On 3/2007
curious7  
 
Posted On Jan 20, 2009

Pigwidgeon:

I have a friend who becomes very ill if she get too much sun, burns easily, and once avoided the sun all together.  A friend read a book about health (I cannot recall the book's title) but the book suggested only exposing parts, of the body, a hand, arm, or leg, and only for limited time, and several times a day.  It does appear this worked for her.



mama bear
Apprentice User Apprentice User Joined On 6/2006
mama bear  
 
Posted On Jan 21, 2009

pigwidge

start slow-2 min a day for a few days.  Then increase to 3...4...5 you get the idea.  if you start to "feel the burn" back it off.  work up to 20 min a day.  i would suggest that you don't increase with every exposure but give it a few days at each time segment to decrease your chances of burning.  Most of all, YOU know your body. LISTEN to it.  If you know you are burning..cover up!

happy sunning!



Bill McDougald
Novice User Novice User Joined On 1/2007
Bill McDougald  
 
Posted On Jan 25, 2009

For any of us that are concerned about sunburns should do as I did and take essential calcium from www.newvision.com. It is ionic and 98% absorbable, same for the essential minerals. This calcium caused my "disease" of sunburning to be cured. I used to get burnt in just 10 minutes and it would last for 3 weeks and after 5 days become "prickly heat" a terribly painful condition. But this wonderful calcium fixed that problem so I can spend even 4 hours in the tropical sun in a swimming pool and not get burned. Oh yes, if I stay out too long, I will get very red and this slight burn lasts only 3 days and doesn't bother me at all. Instead I just put Lavender Oil over it and it heals rapidly. I also use lavender oil for getting a good nights sleep.



Jam Jos
Novice User Novice User Joined On 1/2007
Jam Jos  
 
Posted On Mar 10, 2009

As ChrisH said, when you eat enough vegetables you will not likely burn as quickly.  This is because the antioxidants in certain foods (like vegetables) protect your skin from free radicals formed from the sun.  So if you have very fair skin, start off slow when going out in the sun and make sure to load up on antioxidants from vegetables (juicing them would also be nice).


 
 
 
Posted On Jan 20, 2009

stoic, i think the free pill has a circumference of 1.3 million miles and most likely has a singularity at its core.  


 
ExJohnson
Novice User Novice User, Joined On 7/2008
ExJohnson  
 
 
 
Posted On Jan 21, 2009

to curious7  this website might help you

nadir.nilu.no/.../VitD_quartMED.html


 
jmham
Novice User Novice User, Joined On 10/2007
jmham  
Replied

curious7
Savvy User Savvy User Joined On 3/2007
curious7  
 
Posted On Jan 21, 2009

jmham:

Thank you very kindly.  My problem is trying to convince friends and family about the need for sunshine, and the benefits thereof.


 
 
 
 
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