There are generally two types of sunscreens: chemical and physical. Chemical sunscreens are effective, but some people may be allergic to the main sunscreen ingredients.
If you opt for a chemical sunscreen, choose one which contains safe sunscreen ingredients such as avobenzone (Parsol 1789),Mexoryl or Tinosorb. A chemical sunscreen which contains safe and effective sunscreen ingredients is Anthelios SPF 30 Lotion by La Roche-Posay which contains the active ingredient Mexoryl SX.
Physical sunscreens containing zinc oxide and titanium oxide block more of the spectrum and have less potential to cause an allergic reaction. These sunscreens benefit people with rosacea, eczema or sensitive skin the most. Zinc oxide soothes irritation and reduces redness.
There are many excellent physical sunscreens on the market, and most moisturizers now offer fairly adequate sun protection. Vanicream Sensitive Skin SPF 30 is ideal for babies. Sunscreens suitable for acne-prone skin would be Elta MD UV Clear SPF 46 and Neova Z-Silc SPF 30.
While there are excellent sunscreens on the market, minimizing your skin’s exposure to the sun is still key to slow down photoaging and reduce your risk of skin cancer. Cell toxicity studies by Dr. Yinfa Ma, Curators’ Teaching Professor of chemistry at Missouri S&T, and his graduate student Qingbo Yang, suggest that when exposed to sunlight, zinc oxide, a common ingredient in sunscreens, undergoes a chemical reaction that may release unstable molecules known as free radicals.
Free radicals bond with other molecules, but in the process, they can also damage cells or the DNA contained within those cells. This in turn could increase the risk of skin cancer.
Ma also found that the longer zinc oxide is exposed to sunlight, the greater the potential damage to human cells. This is because the zinc oxide may generate free radicals when exposed to UV rays, and these free radicals can kill cells. Ma also found that light and zinc oxide-exposed cells deteriorated more rapidly than light-exposed cells not immersed in zinc oxide.
Although more comprehensive studies are needed, wearing sunscreen and limiting the exposure of your skin to the sun is the best preventive measure. Another way of reducing the potential side effects of zinc is to use physical sunscreens which are white, not clear.
White physical sunscreens appear that way because the zinc oxide and titanium dioxide particles are too big to be absorbed into the skin. These particles offer sun protection for your skin by physically blocking the sun’s rays.
Clear sunscreens which contain zinc or titanium have these ingredients in the form of nanoparticles. Recent studies have shown that zinc nanoparticles have increased levels of zinc in their blood.
Retinyl Palmitate is a Vitamin A derivative that is closely linked to retinol. Like retinol, retinyl palmitate is safe and effective in night creams as it is converted to retinol on your skin. Retinol in turn increases cell turnover.
However, during the day, the sun’s rays will damage the new skin cells. In addition, retinyl palmitate in sunscreens breaks down in sunlight to form free radicals that can harm cells and cause cancer. Therefore avoid sunscreens which list retinyl palmitate as an active ingredient.
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