补充:SPF也仅仅表示对UVB的防护能力,UVA才是真正的皮肤老化杀手。防UVA还得看PA,或者直接看成分表中的化学防晒成分。
同意上面的白T,有条件穿长袖打伞戴帽比什么防晒效果都好。
”SPF (sun protection factor): measures the length of time a product protects against skin reddening from UVB, compared to how long the skin takes to redden without protection. If it takes 20 minutes without protection to begin reddening, using an SPF 15 sunscreen theoretically prevents reddening 15 times longer -- about 5 hours. (Actually, it may take up to 24 hours after sun exposure for redness to become visible.) To maintain the SPF, reapply sunscreen every two hours and right after swimming.“ |