Sunscreen ratings provide valuable information about the level of protection a sunscreen offers against the harmful effects of ultraviolet (UV) radiation from the sun, but also can be very misleading if you don’t understand what these numbers and letters mean. Understanding these ratings is crucial for effectively protecting your skin from sunburn, premature aging, and skin cancer. Here are the basics you need to know about sunscreen ratings:
SPF (Sun Protection Factor)
- SPF measures the level of protection a sunscreen provides against UVB radiation only, which causes sunburn and contributes to skin cancer risk.
- The SPF rating indicates how much longer it takes for skin to become red when using sunscreen compared to when not using sunscreen.
- SPF 30 means it takes 30 times longer to burn with sunscreen than without. For example, if you normally start to burn in 10 minutes, with an SPF 30 you will have up to 300 minutes of protection. This assumes you are initially applying the correct amount, reapplying every 2 hours or after water exposure, sweating, etc.
- SPF values typically range from 15 to 50 or higher, with higher values offering somewhat greater protection.
- Important to note, SPF is not a linear scale; SPF 30 blocks about 97% of UVB rays, while SPF 50 blocks about 98%.
Broad-Spectrum Protection
- In addition to SPF, it's crucial to ensure that sunscreen provides broad-spectrum protection.
- Broad-spectrum sunscreens protect against both UVB and UVA radiation.
- UVA rays penetrate deeper into the skin and contribute to premature aging, including wrinkles and age spots.
- Look for sunscreens labeled as "broad-spectrum" to ensure comprehensive protection against both types of UV radiation.
Water Resistance
- Sunscreens may be labeled as "water-resistant" if they maintain their SPF level after a certain amount of time spent in water.
- The label specifies the duration of water resistance, typically 40 or 80 minutes.
- Water-resistant sunscreens are helpful for activities like swimming or when sweating, but they still require reapplication after the specified time or after toweling off.
PA Rating
- PA rating is commonly used in Asia, Australia, and some EU counties, sunscreen products and indicates the level of protection against UVA rays.
- The PA rating system uses a "+" scale, with more "+" symbols indicating higher levels of UVA protection.
- For example, PA+ offers some protection, while PA++++ provides the highest level of UVA protection.
Application Amount
- The effectiveness of sunscreen depends on applying an adequate amount to all exposed skin. Keep in mind, all testing for SPF efficacy has been done with ample product applied.
- The recommended amount is about 2 ml of sunscreen per square centimeter of skin.
- Apply sunscreen generously, covering all exposed areas, and ensure even distribution for optimal protection.
Reapplication
- Sunscreen should be reapplied regularly to maintain its effectiveness.
- Reapply sunscreen every two hours when outdoors, especially after swimming, sweating, or towel-drying.
- Even with water-resistant sunscreen, it's essential to reapply after the specified time or if it has been rubbed off or removed.
Sun Protection Tips
- Sunscreen is just one part of a comprehensive sun protection strategy.
- Wear sunscreen when driving and even on cloudy days! If it’s light outside you need sunscreen.
- Be mindful of peak sun exposure hours (usually between 10 a.m. and 4 p.m.). Wear protective clothing, including wide-brimmed hats, sunglasses, and tightly woven clothing that covers as much skin as possible.
- Limit time spent in direct sunlight and take regular breaks indoors or in shaded areas.
- Understanding sunscreen ratings and following sun protection guidelines are crucial for effectively safeguarding your skin against sun damage and reducing the risk of sun-related skin issues.