Researchers agree evidence linking sunburn to skin cancer is overwhelming. But some findings suggest that avoiding sensible doses of sunlight is also harmful. "Sometimes I get the impression my dermatologist colleagues would be happiest if we lived in caves," says MIT's Dr. Richard Wurtman, who recommends daily 20-minute walks at noon to get the sunlight we need.

For those who can't help but equate a suntan with good health, California physician Dr. Zane R. Kime suggests: "The secret is to gradually develop the tolerance. Sunlight will gradually turn your skin tan if you're out and get very moderate exposure."

But an element generally overlooked in the sunburn/skin cancer equation, says Kime, is proper diet. He cites research that implicates a high-fat diet in the development of some cancer.

* "If you look at the average American diet, you see that it is high in fat," says Kime. "You see only small amounts of fresh fruit and not much of the bright colored vegetables."

The result: "We have a population with minimal amounts of protective antioxidants in their skin," says Kime, who recommends using sunscreen products only when prolonged exposure can't be avoided. Other researchers stress sun lotions that prevent sunburning also block the formation of Vitamin D in the skin and recommend 15 minutes of exposure before applying them.

Says Vienna, Va., physician Dr. Russell Jaffe: "The only reason that you are at risk with the sun is being obviously foolish, or obviously deficient. With adequate amounts of Vitamin A (beta-carotene), Vitamin E (tacopherol), selenium, zinc, Vitamin C and glutathione, you are not at risk of skin cancer from sun exposure. But common sense will tell you an acute thermal burn is not a smart thing to do."