Anyone who likes spending extended amount of time outdoors taking in the sunshine knows how terrible a sunburn can be. Even if you don’t get sunburned, most people understand the dangers of powerful UV rays hitting your skin. With extended exposure UV rays you are slowly damaging your skin and increasing your risk of skin cancer.
Luckily sunscreen exists allowing us to spend more time than is considered safe in direct sunlight while protecting our skin. But how exactly does sunscreen keep us protected from the suns harmful rays?
In this article we will explain how sunscreen can keep you protected from the sun, giving recommendations on what to look for when buying it and how to use it effectively.
The Effect Of UV Rays On The Skin
Before going into how sunscreen keeps your protected, you must first understand how UV rays affect your skin without sunscreen protection.
Their are two types of UV rays that hit your skin; UVA and UVB ranging from a wavelength of 290 to 400 nanometers, with UVB rays being the bigger threat to the health of your skin. When these UV rays hit your skin, the energy gets absorbed into the fat and proteins within your skin, creating free radicals which damage cellular structures including DNA.
This damage in the skin cells DNA will cause a burning sensation and appearance in the short term. In the long term it can lead to genetic mutations in your skin cell structure. Since your skin replenishes itself every few weeks, these mutations will get passed on to the new skin cells. As many of you may already know, mutations in living cells is the way that cancer cells eventually form. Sunscreen, however, can help significantly reduce these mutations.
How Sunscreen Keeps You Protected
Most sunscreens have two main types of active ingredients in them; inorganic particles and organic particles. Each of these has a different role to play in the sunscreens effectiveness.
- Inorganic particles, typically zinc oxide or titanium dioxide, form a physical barrier on your skin reflecting UV rays away from your skin.
- Organic particles, like oxybenzone or avobenzone, absorb UV radiation releasing the energy as heat within the organic particles.
So as the UV rays from the sun hit your sunscreen protected skin, the inorganic particles help reflect a large portion of the radiation back into the atmosphere, while the organic particles absorb most of the remaining radiation giving off heat. Therefore, much less UV radiation is making it’s way into the proteins and fats of your skin reducing free radical formation.
Now that you know how sunscreen keeps you safe, keep on reading to understand what you should be looking for in a good sunscreen. With so many products on the market it can be difficult to understand all the jargon.
What To Look For When Choosing A Sunscreen
This can be difficult to understand with so many products available today. In general, you should be looking for a sunscreen with the following properties:
- broad-spectrum protection – this will protect you against both UVA and UVB rays
- has a sun protection factor (SPF) of 15 to 50 – this really depends on your sensitivity to sun burn, higher meaning more protection. More on this below
- is waterproof, even if you don’t plan on going in the water because sweat will also wash some of the lotion off
As long as your sunscreen has these properties you will be making a good choice. Aside from this, there are other factors to consider such as whether certain chemical compounds may react negatively with your skin, but this is really a case-by-case issue that each person needs to discover on their own.
There are also many different forms of sunscreen such as sprays and creams to choose from. As long as you are applying it properly, it really doesn’t matter which type you use, however, creams are considered to be the easiest and safest to use.
SPF is a measure of how well the sunscreen protects against UVB rays which are the more dangerous of the two types of UV radiation. UVB has a shorter wavelength than UVA and thus is the radiation that causes sunburns and most skin cancers.
So as an example, SPF 15 will protect your body against 93% of UVB rays while SPF 30 will protect against approximately 97%. There is no way to protect against 100% but even these amounts are considered safe.
The SPF number also suggests how much longer it will take you to burn in the sun than if you weren’t wearing any sunscreen at all. For example, if you normally burn within 20 minutes wearing not sunscreen, a sunscreen with SPF 15 will make you burn at 1/30 that rate, so it will take you 15×20, or 300 minutes to burn wearing the SPF 15 sunscreen.
How To Properly Apply Sunscreen
According to the Center For Disease Control And Prevention (CDC), these are the guidelines for when and how to apply sunscreen.
When to apply sunscreen:
- at least 30 minutes before you go outdoors so it has time to absorb into the skin
- after swimming or excessive sweating
- every couple hours that you are outdoors to keep a fresh coat on
How to effectively apply sunscreen:
- shake the bottle before application to ensure any clumps are removed
- use one ounce to cover your entire body. For optimal effectiveness, you need approximately 2 mg’s of sunscreen per square centimeter of skin on your body.
- apply sunscreen to all parts of your body that will be exposed to the sun
By following these guidelines you will be maximizing the effectiveness of your sunscreen, significantly reducing your chances of getting sun burn or skin cancer. Don’t think that you are completely protected, however, and seek shade when you can to further avoid over-baking in the sun.