Tag: sunscreen

Sunscreen 101

Published on by CMU Vivid CosmeticsLeave a comment

Sunscreen is a vital skincare product that everyone should apply regardless of weather. As summer is approaching, applying sunscreen is getting more and more important to protect our skin from harmful UV rays. However, choosing the right sunscreen can be tricky, as there are many factors that one should take into consideration to finding the holy-grail sunscreen. Here is a guide to help you choose the sunscreen that will not only protect early skin aging but also decrease the chance of skin cancer. 

Guide to SPF and UV Rays

SPF, or sun protection factor, is a measurement of how long the sunscreen will protect the skin from UV rays. Although people tend to believe that higher SPFs will block significantly higher amount of UV rays, the difference in protection between various SPF is not radical. For example, while SPF 15 can block 93% of UV rays, SPF of 30 can block 97% while SPF of 50 will block 98%. Although SPF is an important factor in choosing a sunscreen, the spectrum of UV coverage is another significant factor to place into consideration. 

UV, or ultraviolet, rays are the primary cause of skin cancer. There are three types of UV rays, UVA, UVB, and UVC but only UVA and UVB rays will damage and cause skin cancer, as UVC rays do not penetrate through the atmosphere. Because UVA and UVB rays will both damage the skin, finding sunscreens containing filters that will block both UVA and UVB rays is absolutely crucial.

Physical vs Chemical Filter

Physical filters protect our skin by reflecting and scattering the UV rays. The only two FDA approved physical filters are: 

  • Zinc Oxide: blocks UVB, UVA1 and UVA2
  • Titanium Dioxide: blocks UVB and UVA2

As shown above, physical filters offer a broad spectrum of protection from the sun and are also better for acne-prone and sensitive skin as the filters do not penetrate through the skin. However, these filters are often the cause of whitecast and difficult application. During summer times, sunscreens containing physical filters require frequent re-application, as the filters rub off easily from sweat and water. 

Chemical filters absorb the UV rays and release them as heat through chemical reaction. Some commonly used, FDA approved filters are:

  • Avobenzone: blocks UVA1
  • Octinoxate: blocks UVB
  • Octisalate: blocks UVB
  • Oxybenzone: blocks UVB and UVA2
  • Octocrylene: blocks UVB and UVA2

These filters are often combined together to cover the various spectrum of the UV rays and to make them more photostable, which means the product will not degrade with exposure to UV ray. Chemical filters have advantages of no whitecast, easier application, and lighter texture. However, they would need to be applied 15-20 minutes before sun exposure. Also, because chemical filters turn UV rays into thermal energy, they can increase the redness on skin. Unfortunately, most chemical filters available in United States tend to penetrate through skin and cause skin sensitivity. New and better filters like Tinosorb S, Tinosorb M and Uvinul T 150 can cover broader spectrum as well as being more stable and less skin sensitizing. However, they are yet to be FDA approved. 

Product Recommendation

Physical Sunscreens

Paula’s Choice CALM Redness Relief SPF 30 – Normal to Oily

  • This sunscreen includes both titanium dioxide and zinc oxide as the main active ingredient. It also contains great moisturizing and calming ingredients like green tea, chamomile, aloe vera, glycerin panthenol. Lastly, this sunscreen is fragrance-free. 

First Aid Beauty Ultra Repair Pure Mineral Sunscreen Moisturizer SPF 40

  • This physical sunscreen also contains titanium dioxide and zinc oxide as active ingredients. In addition to the filters, it contains ingredients like colloidal oatmeal, avocado oil, and allantoin for soothing and calming purpose. While it is paraben-free, it is not fragrance-free. 

Chemical Sunscreens

  • Krave Beauty The Beet Shield
  • This sunscreen contains various chemical filters like Uvinul A Plus, octyl triazone, Tinosorb S and etc. It also contains beetroot extract, vitamin c, resveratrol and EGCG for antioxidants and allantoin for soothing. While this product is fragrance-free, it does contain alcohol for better formulation purpose. 

PURITO Centella Green Level Safe Sun SPF 50 PA ++++

  • This sunscreen uses Uvinul A Plus and octinoxate for chemical filters. Centella asiatica extract and hyaluronic acid provide soothing and moisturizing properties. This sunscreen is also ethanol, PEG, mineral oil, fragrance, and cruelty free as well as being vegan. All the ingredients used have EWG Green level 1-2, making PURITO’s sunscreen a good choice for anyone with sensitive, acne prone skin. 

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