Due to the hormonal changes that take place during recovery, many patients on the Marshall Protocol become sensitive to bright lights and sunlight. They are soon informed that dousing themselves with sunscreen does nothing to affect the production of vitamin D in their skin – hence the need to cover up with thick, dark layers when outside in the sun. “The majority of sunscreens are ineffective in blocking vitamin D production or blocking sun flare symptoms in Th1 patients,” states J.C. Waterhouse of Autoimmunity Research Foundation.

Yet, proponents of high-dose vitamin D continue to blame what they interpret as vitamin D “deficiency” on the fact that the American public wears too much sunscreen. Because they mistakenly believe that sunscreen fully blocks vitamin D production, organizations such as the Vitamin D Council – an organization dedicated to promoting high levels of vitamin D – make a firm point of informing the public that, “The only way to be sure you have adequate levels of vitamin D in your blood is to regularly go into the sun, or use a sun bed (avoiding sunburn).”

Yet dermatologists and other scientists who better understand the properties of sunscreen and vitamin D have been combating these claims for years – arguing over and over again that they are flat out wrong. Three years ago, at the American Academy of Dermatology’s Melanoma/Skin Cancer Detection and Prevention Month news conference, dermatologist Darrell S. Rigel, M.D., clinical professor, New York University Medical Center in New York City, did exactly that.

Rigel’s message: sunscreens do NOT block all of the UV radiation hitting the skin, so that those wearing sunscreen are still able form vitamin D. There is simply no such thing as a total (or even near total) UV block. Even the most effective sunscreens currently on the market let through enough UV to allow for adequate vitamin D formation. According to Rigel, normal vitamin D levels are easily maintained through routine daily activities (even when wearing sunscreen) and a normal diet. “Supplemental vitamin D tablets are typically not needed,” states the scientist.

To support his point he cited a 1997 study published in the Journal of the National Cancer Institute of patients with Xeroderma Pigmentosa (a disease that causes multiple skin cancers in persons exposed to the smallest amounts of ultraviolet radiation), who showed normal vitamin D levels despite virtually no UV exposure.

Rigel went on to argue that no scientific studies exist which prove the statement that low vitamin D levels lead to increases in cancers and other diseases. “The claim is based on a study that finds that overall cancer rates are higher in the northeast United States, a location with lower sunlight levels than many other places in the country. Those making this claim conclude that since the Northeast has lower UV levels, this is the reason why cancer rates are higher in this region. However, several studies prove this theory is false,” says Rigel. These include studies which show that cancer rates are low in the Northern Plains states – areas of the United States that have lower UV levels then the states in the Northeast. Furthermore, several regional studies have shown that the increased levels of cancer observed in the Northeast states are tied to levels of industrial pollutants rather than levels of UV light.

“When we take a close look at these myths and evaluate the facts, the course of action is clear,” said Dr. Rigel. “Until there is science that tells us otherwise, it is imperative that people protect themselves from the sun. Given the fact that the U.S. Department of Health and Human Services has declared UV radiation as a known carcinogen, exposing oneself to it for the sake of vitamin D is not the answer.”

Rigel also challenged vitamin D proponents on their claim that skin cancer is not a dangerous disease, thus rendering protection from the sun unimportant. On the contrary, Rigel argued, one American dies every hour from melanoma, the most serious form of skin cancer.

“As a dermatologist who treats the ravages of skin cancer on a daily basis, it is appalling to me that anyone in good conscience could make the claim that intentional sun exposure – for any length of time – is beneficial,” stated Dr. Rigel. “The fact is, skin cancer is increasing at an alarming rate and scientific research confirms that our best defense is avoiding excessive, unprotected sun exposure.”

Dr. Rigel’s argument supports the fact that the low levels of vitamin D frequently observed in patients with chronic disease are not even the result of deficiency. As described by biomedical researcher Dr. Trevor Marshall in his upcoming paper “Vitamin D Discovery Outpaces FDA decision making”, the low levels of vitamin D observed in patients with chronic disease are simply a result of the fact that when the active vitamin D metabolite (1,25-D) rises as a result of bacterial-induced inflammation, it naturally downregulates levels of 25-D – the precursor form of the substance that is measured in order to detect “deficiency.”

With this information at their disposal for over three years now, why do organizations such as the Vitamin D Council continue to blame what they incorrectly interpret as a “deficiency” of vitamin D among the American public on the use of sunscreen? Is it simply because if they acknowledge that the “sunscreen blocks vitamin D production” myth has been debunked, they will be at a loss to explain how the public could possibly be “deficient” in a substance that is so widely available? After all, the American diet is rich in vitamin D due to fortification of numerous products. Not to mention the reality that most people make about 10,000 units of vitamin D after about 20 minutes of summer sun -100 times more vitamin D than that needed to meet government nutritional requirements.

Note: research by Dr. Waterhouse of Autoimmunity Research Foundation has shown that sunscreens containing the chemical zinc oxide do block vitamin D production in the skin to a certain extent. These sunscreens, particularly those with the highest zinc oxide content (17-20%) provide a means for patients on the Marshall Protocol to better tolerate the sun and participate in outdoor activities.