In 1996, the first members of the baby boom generation turned 50. But unlike their parents and grandparents, the 78 million Americans born from 1946 to 1964 are not accepting aging as a time of inevitable decline. Growing numbers of boomers are trying to stop the clock with remedies ranging from rigorous exercise and dieting to “anti-aging” hormones. Many experts say that fighting Father Time will lead millions of people to longer, healthier and happier lives, and in the long run, reduce the nation's health care costs. But other observers argue that the efforts to stay young will lead to inevitable disappointment and self-delusion.