The promotion surrounding sunscreens has been the promise that they protect from both skin cancers and photoaging of the skin. However, readily available evidence reveals that sunscreens not only increase the risk of skin cancers, including melanomas, but also leave the skin exposed to a higher percentage of the solar rays that actually break down collagen and elastin, resulting in greater photoaging of the skin than without sunscreen use.*
Skin Cancers Increasing in Epidemic Proportions
Over last few decades, the admonition to use sunscreen whenever going outdoors has taken over the headlines, yet melanomas have shown a consistent rise in incidence rate since sunscreens were first introduced. Figure 1 shows the increasing incidence of melanomas in the US, and this rise is reflected throughout the world.1
Figure 1: Melanoma - U.S. Incident Rates
Basal Cell and Squamous Cell Carcinomas
The US National Institutes of Health does not keep track of the numbers of skin cancers that are caused by basal cell or squamous cell carcinomas as it does for melanomas. Therefore, retrospective (historic) case reviews and statistical analyses on pooled data bases need to be utilized to determine the prevalence of these skin cancers. In a Journal of the American Medical Association (JAMA) study published in 2005, doctors stated that they found that the number of women under age 40 diagnosed with basal cell carcinoma had more than doubled in the previous 27 years. The incidence rose from 13.4/100,000 to 31.6/100,000.2 They also stated that, during this same time, the squamous cell carcinoma rate for women also increased significantly.
An analysis published in Archives of Dermatology in 2010 showed that in the 14 years between 1992 and 2006, the total number of procedures for skin cancer in the Medicare (fee-for-service) population increased by 76.9%. The number treated per year rose during this time from 1,158,298 in 1992 to 2,048,517 in 2006. With totals of skin cancer diagnoses and number of patients in the US population much higher than previous estimates, the researchers concluded: "… these data give the most complete evaluation to date of the under recognized epidemic of skin cancer in the United States."3
Our skin is designed to use antioxidants to neutralize the solar radiation as well as increase melanin in the skin as part of its natural protection. Melanin, the brown pigment made by the melanocytes in the basal layer of the skin, is the body's own built-in protective defense, as it effectively absorbs the energy of the UV radiation.4 The use of sunscreens stops the body's natural process of creating more melanin to protect the cells. Sunscreen use also prevents our built-in red warning light – painful sunburn on the skin – from signaling us to get out of the sun. Staying in the sun 10, 20, 30, or 50 times longer than people normally would because a sunscreen chemical is preventing the sunburn consumes the skin's store of antioxidants, leaving the skin open to damage from the radiation. The result has been increased skin cancers paralleling the increased use of sunscreens. One of the reasons that this has occurred is that the first sunscreens only blocked the UVB sunburning rays, and did not block the UVA portion of the solar spectrum. The UVA rays penetrate much deeper than UVB and create reactive oxygen species (ROS) that cause damage at the cellular level, damage that leads to both skin cancers and photoaging.
Combining Sunscreen Chemicals to Create 'Broad-Spectrum' Coverage
Even though this problem was soon recognized, it was not until 2011 that the US Food and Drug Administration (FDA) issued new guidelines mandating that a sunscreen must filter both UVA and UVB radiation in order for manufacturers to put a SPF (sun protection factor) rating on their labels.5 These newer formulated sunscreens are termed "broad spectrum," as they are now required to filter both UVB and UVA solar rays. Since each chemical covers only a specific portion of the solar spectrum, several chemicals must be combined to assure that more of the solar spectrum is filtered. This combining creates diverse problems.
Accelerated Photodegradation: Some of the chemicals or metals used as sun filters actually become inactivated upon exposure to sunlight, a photodegradation that prevents them from being capable of protecting the skin from solar radiation. This photodegradation can occur even more rapidly when chemicals are combined, compared with when they are used by themselves.6
Increased Toxicity: Even more important, research studies have been identifying that chemicals may not be "too toxic" when used individually, but low concentrations of several in combination create new harmful chemical complexes that result in a much more toxic formula. Articles end with the recommendation that all future research on possible toxic effects of sunscreen chemicals has to look at these chemicals in combinations, the way they are now being required to be sold.7
Is Broad Spectrum UV Coverage Really an Answer?
Only 4% of the Solar Radiation that Reaches Our Skin Is UV
With the realization that UVA is more damaging, the promotion currently is: as long as we are using the "broad spectrum" sun filters, we are safe. However, the entire UVA and UVB spectrum makes up only 4% of the total solar radiation that reaches us through the earth's atmosphere. This is another reason why skin cancers have increased with sunscreen use. The far greater amount of radiation that our skin is exposed to is the near infrared radiation (NIR), and NIR constitutes 47% of the solar radiation penetrating our atmosphere and thereby reaching our skin.8 These rays penetrate even deeper than the UVA rays. They go deep into subcellular structures, including the mitochondria, where they create ROS, and that is where the blocking of damaging radiation needs to take place.9 Many new methods have been researched to prevent ROS damage at the mitochondrial level, but no satisfactory solutions have been found to stop the NIR damage – damage that can lead to skin cancers, as well as photoaging of the skin because NIR leads to the destruction of both collagen and elastin.10
Some researchers are investigating an agent called mitoquinone (MitoQ), a quinone similar to coenzyme Q10 (CoQ10) that would work on preventing IR from producing ROS in the mitochondria. Preliminary studies are indicating that it does.11
Sunscreen Chemicals are Potent Endocrine-Disrupting Chemicals
Not only are sunscreens doing the opposite of what they have been promoted for, many journal articles published today are revealing that these chemicals also lead to damaging changes in the species of life that have been tested. Classified as endocrine-disrupting chemicals (EDCs), many of the sunscreen chemicals used are potent estrogens, antiestrogens, testosterones, and antitestosterones.12 In fact, the very commonly used benzophenones and salicylates demonstrate more antiandrogenic activity than that of flutamide, the antiandrogen drug given to prostate cancer patients to stop the influence of testosterone in the effort to slow prostate cancer growth.13
One chemical that is almost universally used in sunscreens is benzophenone-3 (BP3). A generational study on mice showed that it results in both general as well as reproductive toxicity, as shown in Table 1.
These results demonstrate that this common sunscreen chemical affects the entire body, including the liver and kidneys, as well as disrupts normal reproductive development in subsequent generations.14
Benzophenone is Found In 97% of Humans Tested
Due to such excessive use as has been promoted by both sunscreen manufacturers and the medical community, the chemicals are now so ubiquitous in the environment that they are in the bloodstreams of 97% of Americans who were tested, including 90% of Americans who stated that they had never used sunscreens.15
Sunscreen chemicals are also found in household dust, which means that we are breathing them into our lungs, giving them even greater access to the bloodstream.16
In addition, 85% of nursing mothers' milk samples now test positive for sunscreen chemicals, resulting in our children's drinking potent hormones during crucial early development.17
An even bigger problem is that many ingredients belong to a chemical family known as phenols. Bisphenol A (BPA) is a commonly known phenol, which as of 2011 in California and 10 other states is outlawed in baby bottles and baby items such as pacifiers.18
Phenols can pass through the placenta and enter the fetus.19 The fact that offspring of mice and rats exposed to sunscreen chemicals show general, thyroid, and reproductive toxicity means that these chemicals can cause the same harmful changes in our human offspring.20
The Vitamin D Deficiency Pandemic
The promotion of using sunscreens in epidemic proportions has led to what is being described as a worldwide pandemic of vitamin D deficiency, so extreme that there has been a reemergence of rickets, the "17th century disease," in some parts of the world, including America.21 Rickets was given that title as it was rampant when people congregated in cities which became so large that they did not have exposure to sunlight. The vitamin D produced in the skin – our own built-in vitamin D manufacturing plant – in response to solar radiation is a crucial part of our overall health. Adequate vitamin D levels are essential to absorb calcium from the foods that we eat. With low levels of vitamin D, the body cannot adequately regulate calcium or phosphate levels for proper bone formation. This results in soft bones in newborns and toddlers. The children become bowlegged or knock-kneed and are diagnosed with rickets.22 Low vitamin D also results in the body's using parathyroid hormone to pull calcium from the bones for necessary muscle contraction and nerve conduction, which weakens bones even further, rather than building them. Back in the 17th century, once it was realized that lack of sun and therefore diminished levels of vitamin D in the body led to the development of rickets, sun exposure was actively encouraged, including putting babies and toddlers out in the sun, as well as fortifying foods with vitamin D. These practices wiped out that last pandemic.
Today, the message to fear the sunlight, along with the warning to never go in the sun without sunscreen, has led not only to a reemergence of rickets in the 21st century, but also to an increase in the many disease states that develop from low vitamin D levels, including osteoporosis.
Vitamin D plays such numerous roles in most body systems that our entire population is at risk for the many disease states that arise when levels of vitamin D are deficient due to slathering on sunscreen before going outdoors. Newborn infants are at risk for seizures because of low calcium levels caused by low vitamin D.23 Owing to its involvement in glucose metabolism, type 2 diabetes in adults is shown to be associated with low vitamin D levels, and low levels during pregnancy can result in newborns and children developing type 1 diabetes.24 Many autoimmune diseases such as Hashimoto's thyroiditis as well as bowel disorders like Crohn's disease can arise.25
Important in muscle metabolism, vitamin D levels when deficient can lead to fibromyalgia.26 The weakened muscles also can result in bladder incontinence and weak pelvic floors in women, which is linked to an increase in the number of caesarean deliveries that are necessary.27
Part 2 is also online
Dr. Elizabeth Plourde
P.O. Box 14133
Irvine, California 92623-4133
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