What you should know about Sun Protection Factor (SPF)
Everyone is talking about the importance of sunscreen, e.g., how many you should apply, how frequent you should use, and the types of sunscreen available in the market.
Today, we are a bit different. We want to talk about the basics of sunscreen. It is the Sun Protection Factor or also known as SPF.
By simple definition, SPF is the measurement of how good sunscreen will protect your skin from UVB rays. Meaning how well the SPF can protect you from sunburn, damage to your skin, and skin cancer. Guess what? UVB rays are the culprit for all of these. This is when SPF comes into the picture to save your skin!
You need to know that the SPF scale is not linear. If SPF 30 can protect your skin about 97%, how well can SPF 50 protect your skin? It's only 1% higher, which will be 98%. But if you go lower, for example, SPF15, does it go down to 96%? Nope, it will only block the UV as much as 93%. And the recommended SPF by dermatologists is SPF 30.
Can you use higher than SPF 50 sunscreen? Yes, you can, but it does not guarantee 100% UV protection. And it will probably clog your pores even more if it's a physical sunscreen, or it may sensitise your skin if it's a chemical sunscreen (be reminded that this depends on the formulation).
SPF can also be tested to have water resistance ability, and it is frequently used in sports. The water resistance ability can be tested for up to 80 minutes. Meaning, after you've soaked in sweat or jumped in the pool for 80 minutes, the water-resistance ability will be worn off.
Still, how much should you apply? It's about 1.2g for your face or 2-full- fingertips. Sunscreen should cover your neck too so that you can use 2 finger-method for your neck and face.
In the next post, we will talk about the different types of sunscreen available in the market.