Vitamin D research | Gibson Research Corporation (US)

[Laurent de Lyon]

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“Vitamin D” is in quotes here and above because it is not a vitamin at all — in its active form it is the most powerful steroid hormone in our bodies. Though it is surprisingly crucial to both our developmental and ongoing health and well being (as the many clinical studies provided below demonstrate), it is present in it's so-called “active form” in concentrations of only 20 to 50 picograms per liter of human blood (a “picogram” is a trillionth of a gram!)

So just a very tiny bit of this stuff goes a long way!

When human skin is exposed to sufficiently powerful ultraviolet (UV) radiation from sunlight, a form of cholesterol contained in our skin (“7-dehydrocholesterol”) is converted into the precursor of Vitamin D, called “cholecalciferol”. This is then converted by our liver into the inactive bulk storage form of vitamin D that blood tests measure (“25-hydroxyvitamin D”). Although Vitamin D is present in limited amounts in cod liver oil and some fatty fish (salmon, mackerel and tuna), it is essentially unavailable in metabolically useful quantities from dietary sources.

As we age, our skin gradually loses its youthful cholesterol and its ability to synthesize Vitamin D declines over time. Although it has not been widely studied, some reports indicate that by the age of 50, Vitamin D production has fallen to approximately 50% of its original rate, and by the age of 65 production will have fallen to just 25% of its original capability. And independent of age, the skin's melanin pigmentation — either from natural genetic racial coloration or tanning adaptation — acts to absorb much of the sun's visible and ultraviolet radiation. This skin darkening has the beneficial effect of protecting our skin from UV radiation damage, but at the expense of further reducing the skin's rate and capacity for Vitamin D production. (Melanin is 99.9% efficient in absorbing the energy from ultraviolet light, converting it into harmless heat energy.)

“Vitamin D” was misnamed when it was first discovered hundreds of years ago, before we knew where it came from or how it was made. By definition, it is not a “vitamin” because vitamins are not produced endogenously (internally), they must be obtained exogenously (externally) from dietary food sources.

It seems likely that part of the trouble “Vitamin D” has had with capturing
the attention it deserves is due to the fact that, simply by being misnamed a
“vitamin”, it has been lumped in with all of the other vitamins and nutrients,
and thus assumed to be available in sufficient quantity through our diet.

“Vitamin D” isn't even a nutrient! It comes from the sun, not from nutrition.

Vitamin D Science has another problem: Vitamin D is very inexpensive and cannot be patented.

Large and long, many-year double-blind placebo-controlled clinical trials with many participants can easily cost millions of dollars. But since Vitamin D is technically free (just go stand in the sun) or super-inexpensive (about 2.4 cents per day as a dietary supplement), no commercial pharmaceutical company wants to even think about it. Unlike synthetic chemicals to lower cholesterol, control blood sugar, lower high blood pressure or improve sexual performance, no large pharmaceutical company can make money selling vitamin D. And as the studies below demonstrate over and over, maintaining adequate levels of Vitamin D throughout a lifetime is both simple and inexpensive. Prospective study after study shows that Vitamin D is apparently highly effective in preventing many of the health problems that big pharmaceutical firms have invested millions of dollars in developing expensive drugs to cure. This puts such companies in the admittedly awkward position of not being big fans of health.

Vitamin D inexpensively promotes health.

So only University and some hospital affiliated researchers, with comparatively limited budgets, have any interest in exploring the health benefits of Vitamin D. And even when they, again and again, demonstrate surprising benefits from maintaining higher levels of vitamin D ... who's going to market and sell that information? Once again, there's no money in it. So, once again, although all of these professionally prepared reports and studies are freely available for access, download, and printing on the Internet, the general public never knows about is since there's no one running expensive prime-time commercials to sell it.

As you read the studies provided below, I predict that you are going to be
amazed and surprised and perhaps finally skeptical. You're going to wonder “if
this is all true, if this could all be true, why doesn't the public know about it?”

We see expensive commercials every night during prime time for expensive and patented pharmaceuticals that allow older men to urinate more easily and less often, but we never see any similar advertisements mentioning that study after study has shown that simply (and inexpensively) maintaining sufficient levels of Vitamin D can work to prevent rickets (that's well known) but also 17 types of cancer including pancreatic, colon/rectal, stomach, prostate, lung, breast, bladder, uterine, espousal, kidney, ovarian, multiple myeloma, non-hodgkin's lymphoma, and leukemia, lower blood pressure, improve immune system function (prevents colds and flu), autoimmune function, inflammation, multiple sclerosis, autism, allergies, preeclampsia, both type 1 and type 2 diabetes, osteoporosis (also well known) depression, muscle and bone weakness and generalized pain.

Looking at that long list of problems above, you may wonder how something, anything, could possibly “cure” all of those very different disease conditions. But that's thinking about Vitamin D backwards. Vitamin D doesn't “cure” anything. NONE of those things are supposed to go wrong in the first place. So Vitamin D simply allows our bodies to work the way they were designed to . . . because our bodies were designed to have much more Vitamin D circulating through them than most indoor-living Westerners do today.

The human race evolved, developed and emerged in sub-Saharan equatorial East Africa where, year round without seasons, we received the sunlight we needed everyday for our skin to manufacture all of the Vitamin D hormone we required from our skin's natural cholesterol. When we migrated away from the equator, natural selection quickly eliminated most of the melanin pigmentation from our skin in an attempt to compensate for the much weaker levels of UV radiation available for making Vitamin D. But then we went indoors and have been inadvertently starving our bodies of Vitamin D ever since.


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Vitamin D IS HIGHLY TOXIC when ingested in
extremely high doses daily for many months !!!
Our skin's natural sunlight-driven production of Vitamin D is internally regulated to limit the maximum rate at which Vitamin D can be produced. It has been estimated that approximately 10,000 to 20,000 IU of Vitamin D is generated by 20 to 30 minutes of full body exposure in direct overhead sunlight. Beyond that, continued exposure begins to degrade any additional Vitamin D produced to limit its total daily production. It is, therefore, impossible to overdose on Vitamin D obtained from sunlight, and there is no record that it has ever happened.

But no such limitation exists when high-potency Vitamin D supplements are ingested orally.

Although it is quite difficult to overdose on Vitamin D, YOU MUST TREAT IT WITH RESPECT. Its value lies in its power, but you want it to improve and not compromise your health. Follow the labels on supplements, educate yourself about dosages, if at all possible test your blood's Vitamin D level, check with your doctor, and be responsible.

John Jacob Cannell, M.D. and executive director of the Vitamin D Council has this to say about Vitamin D Toxicity.

The Merck Online Medical Manual has the following to say: “Because synthesis of 1,25(OH)2D (the most active metabolite of vitamin D) is tightly regulated, vitamin D toxicity usually occurs only if excessive doses (prescription or megavitamin) are taken. Vitamin D 1000ug (40,000 IU)/day produces toxicity within 1 to 4 months in infants. In adults, taking 1250 ug (50,000 IU)/day for several months can produce toxicity.”

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Source : https://www.grc.com/health/vitamin-d.htm