The Science Behind Tanning

Your friend texts you, “the UV is 8. 8!” You respond, “Come over right now we’re tanning.” When your friend shows up, your mom passes you the sunscreen. You throw it to the side, because who needs protection.

     Marit Peterson, Class of 2022, knows just how important sunscreen is. When she was young, Peterson was diagnosed with advanced melanoma and given 6 months to live. After going through surgery and immunotherapy Peterson beat cancer.

    Today, she is 15 years cancer free and an advocate for skin cancer prevention, which includes convincing girls to prioritize protecting their skin from dangerous UV rays.

     The UV index measures the intensity of Ultraviolet rays from the sun.

     According to Tropic Labs, a beach brand dedicated to spreading information about the dangers of the sun, “Your skin needs both UVA and UVB light to tan. That is because UVA light darkens the pigment cells already inside your skin vs. UVB light which causes your skin to make more pigment cells.”

     While tanning, these UV rays penetrate the skin and affect skin cells. When the skin feels to be “heating up,” it is the UV rays directly affecting the cells that are working to protect the person.

     “These interactions are actually a huge threat to skin cells. When UV rays from the sun reach these skin cells, they kick into protection mode, distributing darker pigment cells (melanocytes) to those cells on the surface as a form of protection. The pigment blocks UV radiation from hitting cells’ most valuable parts.” Marit said, “And while this may seem safe, the increase of the production of melanin creates a higher chance of DNA mutations, which lead to skin cancer.”

        The higher the UV, the higher the chances of the UV rays damaging skin. The main way to protect the skin is to wear sunscreen.

   “Sunscreen creates a protective layer that reflects the UV rays from the sun.” Marit explained, “My daily regimen includes an SPF 30 facial moisturizer that I put on immediately after washing my face in the morning and reapply every two hours if I know I’ll be in the sun. Even on overcast days, the UV rays can penetrate through the clouds and into the skin.”

      However, in the average drug store, there are many different sunscreen options, all with different SPFs. SPF is the measure of the sunscreen’s protection from UVB rays, it does not measure UVA rays. If the label says “broad spectrum” it offers protection from both UVA and UVB.

    According to SkinCancer.Org, SPF works by elongating the time it would normally take to burn. Say a person usually burns after 10 minutes, with SPF 30 sunscreen, they would then be able to stay in the sun without burning for around 300 minutes. This is all considered in ideal circumstances, as many people burn at different rates.

      “SPF 15 protects you from about 93.3% of the UV rays. Wearing SPF 50 is even better, as it protects you from about 98% of the UV rays.” Marit said, “My favorite sunscreen brand is Sun Bum (the one with the monkey). It smells like coconuts and does not feel greasy on the skin, which is a reason some do not like [to wear] sunscreen.”

      Before going out to tan, consider what that sun really does to your skin and if the temporary golden is worth the risk of long-term effects.

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