Leila Denmark, a pediatrician in Alpharetta, Georgia, sees about 20 patients a day. She also loves to hike and play golf. No big deal? Well, Denmark turned 100 this month! She's the oldest practicing doctor in the country, according to the American Medical Association. Denmark first went to work in 1928. Her secrets for a long life: "You have to eat right," she told TFK, "and you have to love what you do."