Everyone knows that you should wear sunscreen when heading outdoors. Even if the sun is behind the clouds, you can still get a sunburn. While it’s common knowledge that sun exposure, and the burns it may leave behind, can eventually cause skin cancer, most don’t know how sunscreen protects us and keeps us from getting melanoma. So, how does sunscreen work and what do we need to know about the different varieties?
What Types of Sunscreen Can You Purchase?
Sunscreen can be bought in a variety of forms. These include:
Each of these also can be purchased with a variety of organic and inorganic chemicals, or just as organic.
Sunscreens that are made of inorganic chemicals have properties that can reflect or scatter sunlight away from the skin. Where organic, or carbon-based, properties absorb the UV rays before they can enter our skin. Each has its own pros and both work well at protecting us from UV rays.
How Sunscreen Works
Ingredients, such as zinc oxide and titanium dioxide, physically block the sun from entering our skin. The metallic qualities of these compounds reflect the UV rays and don’t allow them to penetrate our bodies. Instead, the rays bounce off areas of our body where sunscreen was applied.
Sunscreens also have organic chemicals such as avobenzone and oxybenzone. Where the inorganic compounds reflect the UV rays, these organic chemicals absorb UV rays, break them down, and then release the rays as heat.
What’s the Difference Between UV’s?
There are two forms of UV radiation that are talked about when it comes to sunblock: UVA and UVB.
SPF protects against UVB radiation by deflecting the rays and preventing sunburns. It also protects against skin cancer.
UVA’s, also noted on many sunblock brands, is not a rated form of radiation; however, inorganic chemicals will deflect both UVA and UVB rays.
UVA’s are just as dangerous as UVB’s. They penetrate deep into the skin and leave behind irreversible damage. These include wrinklings, age spots, and increased risk of skin cancer.
What is SPF?
SPF stands for Sun Protection Factor. Most doctors and medical organizations agree that we should wear, at a minimum SPF 15.
SPF 15 protects against approximately 93% of UVB’s. SPF 30 protects against 97% of UVB rays. While no SPF can block 100 percent of UV rays, using a sunscreen provides immense protection against these dangerous rays.
While there are sunscreens on the market that are sold as SPF 50 or higher, there are no known benefits to purchasing them. There has also been no evidence that an SPF rating higher than 50 provide any more protection than the SPF 50 product itself.
The way SPF works is that it equates to roughly how long a person’s skin will turn red, wearing the product, as opposed to not wearing it. Therefore, if you wear an SPF 15 sunscreen will prevent your skin from getting red for approximately 15 times longer than it would without wearing it.
The same goes for an SPF 30 sunscreen. It provides 30 times longer protection against the sun’s damaging rays.
How Often Should Sunscreen Be Reapplied?
The current recommendation is to reapply sunscreen every two hours or after swimming. Since most people don’t apply sunscreen evenly, the two-hour rule is a safeguard. While you may have enough sunscreen on to protect you for several hours, it doesn’t hurt to reapply it often.
Is Applying a Chemical to My Skin Safe?
While sunscreens do contain chemicals, the risk versus the reward needs to be considered.
Some studies have found that oxybenzone that is absorbed into the skin is found in urine hours after the sunscreen was applied. If you are not a proponent of using these chemicals, it is recommended to wear a hat, sunglasses, and UV protective clothing when going outdoors.