It's the first day of summer and the day the first bikini hit the beach back in 1946. The bikini has given sun-bathers more skin to tan and girl watchers more girl to watch. But years of sunburns have taught us that beautiful tans lead to early aging and serious skin problems. Sunburns cause skin to age faster and increase chances of skin cancer. While there's no safe way to tan, you can protect yourself by always wearing a sunscreen of SPF-15, or higher. Use it year-round -- rain or shine (UV rays pass through clouds and through clothes, too). (T-shirts give only 2 percent of the protection needed.) SPF stands for "sun protection factor." These numbers multiplied by 10 tell how many minutes it's effective. SPF-15 lasts 150 minutes, SPF-30 300 minutes, and so on. And that's the On The House tip for today.