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Is Your Sunscreen Causing Cancer?

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The majority of sunscreens on the market today are more harmful than beneficial. Sunscreens are designed to decrease your risk of skin cancer and allow you to enjoy the sun without worry. Unfortunately, most modern day sunscreens may increase your risk of cancer and disrupt the functioning of your hormones.

What causes skin cancers?

Ultraviolet radiation from UV-A and UV-B rays from sun exposure is the number one cause of skin cancer. Smoking, HPV (the virus that causes genital warts) and artificial light from tanning beds are also associated with an increased risk of skin cancer.

UV-A vs. UV-B

UV-B rays penetrate only the epidermis (the outer most layer of the skin) and increase your risk of cancer by direct photochemical damage to your DNA, resulting in mutations in your genes. These mutations contribute to wrinkling and aging of the skin by degrading elastin and collagen.

UV-A rays penetrate deeper into the dermis (the 2nd major layer of the skin) and can contribute to the development of cancer by increasing reactive oxygen species, which can, in turn, damage your DNA.Therefore, when choosing a sunscreen, you should opt for a sunscreen that blocks both UV-A and UV-B rays.

Origin of sunscreen

Franz Greiter first invented sunscreen in the 1940s. The active component consisted of zinc oxide. Zinc oxide acts as a physical barrier that sits on the surface of your skin; it offers the same protection as wearing a long sleeve shirt. Zinc oxide has been approved by the FDA and has been shown to be photo-stable against both UV-A and UV-B sun-rays. Because it is not absorbed into the skin, it is nonirritating, non-allergenic, and non-comedogenic (does not cause acne).

If zinc oxide is so effective, why is it rarely used today?

Aesthetically, zinc oxide is a disaster. Because it is not absorbed into your skin like most sunscreen products, you're left with a pasty white substance all over your skin with each application.

Your typical sunscreen product

Let's first examine how your typical sunscreen product works. First, unlike zinc oxide formulations, which sit on the surface of your skin, they are partially absorbed through the skin. This means that any harmful ingredients in your sunscreen will have a systemic effect. Your typical "banana boat" sunscreen is full of parabens. Parabens may increase the rate of breast cancer and interfere with the male reproductive system. Parabens can also antagonize androgens (testosterone) and wreaks havoc on your body's hormones. Oxybenzone and retinyl palmitate are two other harmful ingredients contained in many sunscreen products. Oxybenzone has been linked to contact uticaria (hives), contact dermatitis, and degradation of the epidermis. Retinyl palmitate has been shown to increase the rates of cancer in combination with UV-A rays.

Are typical sunscreen products protective against skin cancers?

Studies are conflicting. The study by Westerdahl, Ingvar, Masback, and Olsson showed higher rates of melanoma in individuals who wore sunscreen compared to those who didn't. The authors concluded that those who wore sunscreen most likely spent more time in the sun which would be the reason for the results. A meta-analysis of 9067 patients from 11 case-control studies found no association between sunscreen use and the development of malignant melanoma (the most deadly skin cancer).

Are my only options a protective pasty white substance and a potentially harmful, but aesthetically appealing sunscreen?

No! There are better ways to stay protected from the harmful effects of the sun. Enter micronized zinc oxide. Micronized zinc oxide has the safety profile of traditional zinc oxide sunscreen and is as aesthetically appealing as modern day sunscreens. When micronized zinc oxide is applied in the form of a lotion it is not absorbed into the body, does not enter the bloodstream and has no dangerous side effects unless it is inhaled. For this reason, I recommend avoiding any "spray" products containing micronized zinc oxide.

Why are micronized zinc products not as popular?

It likely comes down to economics and a lack of education about skin cancers and sunscreens. Micronized zinc oxide sunscreens are more expensive and difficult to source than typical Banana boat sunscreen.

In closing, exposure to UV rays from the sun can cause premature aging and increase the risk of skin cancers. Most modern day sunscreens have many potentially harmful ingredients that should be avoided. I recommend staying hydrated, increasing your intake of omega 3 fatty acids and applying micronized zinc oxide based sunscreens to protect yourself and your family from premature aging and skin cancers.