How Often Should We Use Sunscreen?
The sun can be both beneficial and detrimental to your health. Like many other things we need in life such as food, too much of the good stuff makes it bad for us too. Getting exposed to just the right amount of sunlight everyday, at the right time of day, helps our bodies maintain a healthy level of Vitamin D. This particular vitamin is supplied by the skin as it captures sunlight and turns Vitamin D into a form that is useful for the body, particularly in regulating calcium and in supporting proper cell communication.
However, sun exposure can also lead to several adverse health effects, including developing skin cancer. The Skin Cancer Foundation notes a projection that at least 1 in every 5 Americans will develop skin cancer in their lifetime.
How do You Get Sunburned?
Sun exposure puts you at risk for suffering damages caused by two types of ultraviolet radiation, UVA and UVB. UVA rays penetrate the deeper layers of your skin, and are what causes wrinkles, sun spots and other longer-term damages to your skin. UVB rays, on the other hand, affect the epidermis or the outer layer of the skin, and is what causes you to get sunburned. UVB rays are also the primary cause of developing skin cancers, the effect of which are aggravated by UVA rays although, some experts argue that UVA rays also lead to skin cancers.
When you get too much sun exposure, you get sunburned. This is because the skin reacts to the heat and cellular damage afflicted by the sun to your epidermis. The skin cells and capilliaries underneath which are found in the dermis and the skin’s subcutaneous layer react quickly to the damage. As a result of this reaction, there is a significant blood rush which causes the redness associated with sunburn.
Not getting sunburned, however, does not mean that your skin did not obtain any damage.
What’s in a Sunscreen?
Sunscreens are the best defense that your skin can get to block skin from getting sun damaged. Sunscreens work two different ways. Chemical sunscreens work by absorbing the UV radiation which then triggers chemical reactions with the sunscreen to take place, turning the once harmful UV rays into non-damage inducing heat. Mineral sunscreens, on the other hand, act as barriers between the sun and your skin thus, literally shielding your skin from sun exposure.
Sun Protection Factor (SPF) in sunscreen is what makes it such an important part of your daytime skincare routine. SPF in sunscreens is computed based on the average period of time it takes for several people of different skin types to get sunburned without sunscreen and to get sunburned without. Such that when the label reads SPF 15, it means that, the sunscreen is able to provide 15 times longer period of time for a person using it to get sunburned than when sunscreen is not applied. For higher SPFs, however, this does not automatically follow. In fact, some skin experts say that anything higher than SPF 50 will have the same effect as an SPF 50 sunscreen.
There are 9 sunscreen ingredients most commonly used in commercial sunscreens today, most of which are formulated from 2 to as much as 6 different combinations to block off both UVA and UVB rays. These ingredient include Oxybenzone, Octinoxate, Homosalate, Octisalate, Octocrylene, Titanium Dioxide, Zinc Oxide, Avobenzone, and Mexoryl SX. Oxybenzone and Avobenzone are the most irritating, with the first also being the most toxic of all. The safest and most preferred are Titanium Dioxide and Zinc Oxide, both of which are mineral sunscreens, non-irritating and provide broad spectrum protection.
You May Like: How Can You Prevent Sunburn?
How to Estimate Frequency Of Application?
Higher SPF means better performance in blocking out the UVB rays too. What used to be a recommended minimum SPF for your daily sunscreen, SPF 15, is now under debate as others argue it shold be at least SPF 30 to block out an estimated 97 per cent of UVB rays compared to only 93 per cent for the old standard.
Think of SPF as a multiplier for when your skin begins to get sunburned when lathered with a particular type of sunscreen. If your sunscreen reads SPF 15, that means that when you use it, it will take your skin 15 times longer to get sunburned than when you don’t have sunscreen on. To be more specific, if it takes your skin approximately 15 minutes to get sunburned, it will take you over three hours to get burned with this particular sunscreen on.
Sounds simple enough? Not exactly, because the SPF won’t be able to tell you everything you need to know about keeping your skin shielded from the sun. There are other factors to consider – like sweating, soaking in water, even clothing (some types of clothes now have UV protection too) – all of which affect how and when you get sunburned.
Therefore, skin experts recommend that, as a general rule, you should apply sunscreen at least half an hour before sun exposure and reapply sunscreen every two hours thereafter.
Read Also: How Can You Treat Sunburned Skin?
Don’t leave your health to fate. Sunscreens, sun glasses, broad brimmed hats, protective clothing — where sun protection is available, it’s in your best interest to use them.