Marilu Henner had her last bite of cheese 39 years and one day ago. I celebrated my health birthday yesterday," said Ms. Henner ... as - inevitably - the details began flooding back. "August 15, 1979, I gave up dairy products. It was a Wednesday. The weather that day was beautiful. And I went to see a doctor who told me, 'You have to give up dairy products. You're not going to be healthy unless you give up dairy.'" Ms. Henner is famous for playing the cabby Elaine Nardo in the 1970s sitcom "Taxi." She has also written 10 books (mostly about health and well-being); starred in another TV series, "Evening Shade"; and appeared in several movies and Broadway shows. But thanks to a "60 Minutes" segment in 2010, Ms. Henner has become famous for what neuroscientists call highly superior autobiographical memory - the ability to recall past life experiences, including day of the week and date, with remarkably vivid detail. "You don't know for how many years people have been talking about my memory," Ms. Henner said. "And then they'll ask me about something from two weeks ago and I tell them, 'You can go a little further back than that.'" Back, say, to when she learned about being cast in "Taxi." It was June 4, 1978, a Sunday.