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Sunblock 101

The American Cancer Society recommends using sunscreen everyday, not just during summer or when spending long periods of time in the sun. It is especially important to use it on the face to protect from harmful UV radiation and premature aging. Although exposure to sunlight is healthy in small amounts and can be beneficial by increasing the body’s natural Vitamin D production, long term exposure to UV radiation is what causes skin irritation, sunburns, and premature aging.

Benefits to using sunscreen:

  1. Protect against skin damage & sunburns

  2. Prevent premature aging

  3. Prevention against skin cancer

  4. Protection against blue light pollution from phone and computer screens

UV Rays are non-visible ultraviolet light energy emitted by the sun. Of all the light energy that reaches the Earth’s surface, UVA makes up 95% and UVB makes up 5%.

UVA- premature aging/ wrinkles

UVB- sunburn, skin cancer, tanning


Suncare Basics:

  • Look for Broad Spectrum Sunblock:

When choosing sunscreen, look for “Broad Spectrum” sunscreen that protects against both UVA and UVB Rays.

  • According to the American Cancer Society you need at least SPF 30 or more for adequate protection:

    1. SPF 15 filters out 93% of UVB rays

    2. SPF 30 filters out 97% of UVB rays

    3. SPF 50 filters out 98% of UVB rays

    4. SPF 100 filters out 99% of UVB rays

  • Follow directions on the label. Reapply Sunscreen every 2 hours or after physical activity that may cause it to rub off:

Every sunscreen is different! For the best effectiveness, be sure to apply according to the directions. Most sunscreens advise reapplying every 2 hours. Sunscreen is prone to wearing off over time, whether due to water, sweat, or rubbing off on clothing or towels. Water and sweat resistant sunscreens typically last 40-80 minutes and require reapplication to protect you from the sun.


FAQ 1 : Chemical or Physical Sunscreen, which one is better?

A: The correct answer is: whichever one you choose to use! Sunscreen is personal preference, however the best sunscreen for You is the one that you actually use.

Physical Sunscreen: Physical sunscreens are made with a mineral such as zinc oxide or titanium dioxide to reflect the sun rays.


-less irritating

-more moisturizing

-safe on babies and during pregnancy

-won’t sting if it gets into your eyes

-immediate sun protection (you don’t have to wait 15-30 minutes before going outside)

-protect against blue light (from phones, laptops, and sun)


-doesn’t last as long (rubs off easier from sweat, water, and clothing)

-more sunscreen is required since it forms a protective layer to ‘block’ UV rays

Chemical Sunscreens: Chemical sunscreens are formulated with active ingredients to absorb the harmful UV rays, converting it into heat to be dispersed by the body.


-typically easier to apply and absorb into skin (less white residue)

-better for activities or sports where you sweat more

-more water resistant for swimming


-can be irritating to sensitive skin (especially those with higher SPF)

-can sting if it gets into your eyes

-some people prefer to have less chemicals on their bodies

FAQ 2: So... How much sunblock do I need to apply?

According to the Skin Cancer Foundation, you need to apply roughly two milligrams of sunscreen per square centimeter of skin, which is around 2 tablespoons of sunblock for your face and body, more if you have a larger surface area to cover. For your face, you need about a nickel sized amount of sunblock.

For spray on sunscreens, they recommend to apply it until an even sheen appears on the skin.

FAQ 3: Does sunblock prevent my body from producing Vitamin D?

According to the Skin Cancer Foundation, although sunblock is designed to protect your skin from overexposure to UVB rays, there is no evidence to suggest that sunblock prevents people from metabolizing vitamin D. Since 2-7% of UVB rays are still able to penetrate the skin, it is able to convert some of the light into Vitamin D.

According to Anne Marie McNeill, MD, PhD , the risk of unprotected sun exposure outweighs the benefits of Vitamin D. She says "even a small amount of time, 10-15 minutes of unprotected sun exposure can damage skin. Skin damage is cumulative and every bit of this damage adds up throughout your lifetime, producing more and more genetic mutations that keep increasing your lifetime risk of skin cancer."

Environmental Health Considerations:

Avoid sunscreens that list oxybenzone, octinoxate, octocrylene, or nano-sized zinc and titanium dioxide as their active ingredients since they have been known to be toxic to the environment and cause damage the development of coral reef larvae. Certain places such as Hawaii, Florida, and the US Virgin Islands have banned sunscreens with these chemicals listed as active ingredients to protect marine wildlife. Look for an EWG (Environmental Working Group) rated product that has been approved for consumers to help minimize your impact on the ecosystem!

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