Neither SPF nor PA is definitively "better"; they protect against different types of UV radiation. To achieve optimal sun protection, you need a sunscreen that offers both.
Understanding SPF and PA
-
SPF (Sun Protection Factor): Measures a sunscreen's ability to protect against UVB rays, the primary cause of sunburn. A higher SPF number indicates greater UVB protection. For example, SPF 50 offers significantly more protection than SPF 15. [Source: Multiple sources, including Paula's Choice and Nativ Essentials]
-
PA (Protection Grade of UVA): Measures a sunscreen's protection against UVA rays. UVA rays penetrate deeper into the skin, causing premature aging and contributing to skin cancer. PA ratings are represented by "+" symbols (PA+, PA++, PA+++, PA++++), with more "+" symbols indicating higher UVA protection. PA++++ offers the highest level of UVA protection. [Source: Colorescience, Beauty Harbour]
Both UVA and UVB rays contribute to sun damage, leading to sunburn, premature aging, and skin cancer. Therefore, choosing a sunscreen that protects against both is crucial. A high SPF alone is insufficient; you also need significant UVA protection, indicated by a high PA rating. [Source: Initial reference text]
Choosing the Right Sunscreen
The best sunscreen for you is one that provides both broad-spectrum protection (meaning it protects against both UVA and UVB rays) with a high SPF (at least 30) and a high PA rating (PA+++ or PA++++). [Source: Multiple sources, including Paula's Choice and Reddit discussions]
- Example: A sunscreen labeled "SPF 50, PA++++" offers excellent protection against both UVA and UVB rays.
While some sources might express a preference (like one Reddit user favoring PA-rated sunscreens), the ideal approach emphasizes broad-spectrum protection with both high SPF and high PA ratings. Don't solely rely on one system; consider the comprehensive protection offered by a combination of both.
