We often see SPF on UV Protection, but what does it mean?
SPF is known as Sun Protection Factor, which indicates how much protection a product offers against UVB light, the higher the number, the less UVB passes through, which is responsible for the color change in our skin after spending time outdoors.
Meanwhile, the SPF number is the amount of time it takes for the skin to redden upon exposure to the sun with protection as opposed to the amount of time without protection. For example, If our skin would burn after 30 minutes in the sun, meaning apply sun protection with an SPF30 would prevent our skin from sunburning for around 300 minutes. However, it is wrong to think that the higher the SPF, we can spend longer times in the sun.
Yesss, I know what you are thinking! But It doesn't work that way!
SPF 15 sun protection blocks 93% of UVB rays. SPF 30 blocks 97% of UVB rays, while SPF 50 blocks 98% of UVB rays, no sun protection can block all UV rays. So, while you're hesitating to pick sun protection, you can go for SPF 20 instead of SPF 50 as it is the best recommendation for daily use, but if you are spending a lot of time in direct sun such as beach or jungle hiking, you can go for SPF 50.
So, SPF will protect our skin from UVB rays, which cause sunburn, damaged skin and can contribute to skin cancer.