What is SPF?
SPF is a measure of how well a sunscreen protects against UVB rays. In recent years, SPF ratings have been extended to encompass the UVA spectrum as well.
SPF 15 blocks 93 percent of UVB rays and SPF 30 blocks 97 percent—a modest improvement over SPF 30+. Both provide good protection in normal conditions, but if you’re going to be outside in intense sunlight (like during a beach day or while skiing), it’s worth upgrading your SPF to 50. Every person exposed to the sun, regardless of their skin tone or skin type, should use sunscreen. In general, one-half a teaspoon of sunscreen, or two finger lengths, is necessary for your face and neck, and one ounce is sufficient for your complete body.
How to Use SPF?
To get the best results, always apply a small amount of sunscreen to your face and neck 15 minutes before going outside. If you’ll be at the beach or pool for prolonged periods of time, reapply every two hours or after swimming. For even better protection, wear sunglasses and a hat to shield yourself from UV rays.
What's in Your SPF?
To understand what's in your SPF, it's important to understand what the letters mean. SPF stands for "sun protection factor." It measures how much sun exposure you can tolerate without getting burned under a given amount of time. For example, if you could normally get burned in 10 minutes without sunscreen and reapply every two hours while wearing an SPF 30, then you would need to stay out in the sun for 300 minutes (5 hours) with no sunscreen on before burning with an SPF 30 formula on.
The UVA rating is a measure of how well your sunscreen protects against ageing and wrinkling caused by long-term exposure to ultraviolet rays. UVB is responsible for sunburns, but UVA penetrates deeper into the skin and causes damage over time that contributes to wrinkles and age spots as well as melanoma, which is the deadliest form of skin cancer.
We hope this guide has helped you understand the importance of SPF, and the many ways to get it in your life. Just remember that no matter how you choose to do it—with sunscreen, a hat, or a long-sleeved shirt—it's important to protect yourself from those harmful UV rays!