Do You Need Sunscreen?
- xoxoavenue24
- Jun 3, 2021
- 4 min read
It's during these warm and sunny months that many North Americans start to purchase new sunscreen for the hot summer months. Many however, decide not to wear it. There are many misconceptions towards the usage of sunscreen and how it works. So let's clear up the big question: do you need sunscreen?
What is sunscreen?
According to the FDA, Sun Protection Factor (SPF) is a measure of how much solar energy (UV radiation) is required to produce sunburn on protected skin (i.e., in the presence of sunscreen) relative to the amount of solar energy required to produce sunburn on unprotected skin. As the SPF value increases, sunburn protection increases. This means that selecting the appropriate amount of SPF will prevent sunburns!
The way that SPF is calculated in laboratories during testing is by devising how long is takes for UV damage to cause redness on the skin with sun screen versus how long it takes without sunscreen. I.e. if it takes 75 minutes for the skin to produce redness on the skin with sunscreen, and it takes 5 minutes for the skin to produce produce redness without protection, the SPF is 15. While everyone's burning time without protection is different, it's important to wear Sunscreen daily! Below is an image displaying the efficacy of each SPF.
It is however, a misconception to believe that SPF can determine when you need to reapply. Always follow the instructions on your SPF. Despite the varying wavelengths of UV throughout the day, Sunscreens typically recommend reapplying every 2 hours in sun exposure, and more frequently if you are swimming or come into contact with water. UV rays vary throughout the day. Some cause UVA or UVB damage. UVB rays are typically what cause burning on the outer most layers of the skin. About 95% of UV comes from UVA, which goes deeper into the skin and causes premature aging.
UV Rays
In our Canadian environment, UVB rays are strongest in the Summer, but can cause UV damage year-round. Highly reflective surfaces like ice and snow can cause burning. As previously mentioned, UVB rays are easier for us to notice. UVB damage is visible to us because it shows up as a sun burn or a slight tan on the skin.
UVA rays are a silent attacker. They are consistent in strength year-round. They can penetrate through clouds, fog, and are present despite the lack of sunny weather. UVA rays can even pierce through windows! It is difficult to detect, but UVA causes deeper damager to our skin and photodamage.
Chemical vs Mineral Sunscreen
Sunscreen works hard to protect your skin, but there's two different kinds you can purchase. There are Chemical and Mineral sunscreen.
According to Paula's Choice, here are the major differences between Mineral and Chemical Sunscreen:
Mineral Sunscreens:
Begin to work immediately on application, but must be absorbed to be most effective and to ensure they don’t wipe off on clothing.
Have almost no risk of irritating skin.
May leave a white cast, especially on darker skin tones, but the best pure mineral sunscreens go on almost sheer.
May need more careful, liberal application because of the way they work in formulas. So, go ahead, slather these on for brilliant protection!
Do not penetrate past skin's uppermost layers.
Synthetic sunscreens:
Begin to work immediately on application, but must be absorbed to be most effective and to ensure they don’t wipe off on clothing.
Are generally found in products with thinner textures.
Tend to be preferred for water-resistant formulas because they don’t turn milky-looking when you sweat or get wet. But, as with any sunscreen, you must reapply them often.
Can be sensitizing for those with extra-sensitive skin.
Can penetrate the skin and be absorbed in small amounts that are not shown to have health risks.
What is Sun Damage and How does it Work?
UV rays from the sun cause the production of free radicals. Free radicals damage the skin and can cause premature aging. Free radicals are unstable atoms. Atoms become unstable when there are an uneven amount of electrons orbiting around the atom. When the electron loses its partner, it becomes a free radical. There are unstable oxygen atoms become free radicals. The free radical will steal a replacement from a surrounding molecules or a compound. This causes a domino effect of damage. When free radicals are unstable, they attack the skin and cause oxidative stress. Excessive free radicals in the body attack the cell membranes. This causes tissue damage or even breaks strands of DNA into mutations or cellular death. If enough damage occurs, premature aging begins. This is because oxidative stress plays a pivotal role in accelerating the aging process.
Damage from the sun is call photoaging. DNA changes occur are a cellular level when there is no protection on the skin from UV. Minor changes in the skin include brown spots, wrinkles, broken capillaries, and uneven skin texture. Severe damage can also lead to skin cancer.
The Bottom Line
You need sunscreen all day every day! Skin is the human bodies largest organ. Our skin is meant to protect us from microbes and the environment. So let's do ourselves a favour and apply some sunscreen!
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