Dr. Colin Depp fascinated the recent monthly meeting of Senior Olympic participants and their guests. His topic was “The Science of Successful Aging.” The audience, comprising mostly athletes, was especially interested in ways to healthful habits. Depp is an assistant professor at the Stein Institute for Research on Aging, connected with and located on the UCSD campus. A native of New York and a psychologist, he joined the faculty of the research department only three years ago. Explaining that aging is still considered a mystery without a clear definition, he quoted philosophers such as Cicero, who used the word “adapt,” as well as others who have tried to describe an ethereal condition. The professor and his associates have studied one book, “Successful Aging,” written by Rowe and Kahn in 1987. They detailed 29 definitions of aging through as many studies on the subject. Theories differ on the being able to pinpoint specific subjective qualities. Surprisingly, only about 20 percent of the aging process is linked to genetics, with at a minimum 70 percent the result of one’s lifestyle. And lifespan always involves “tradeoffs.” Making good choices are the ones that extend life. Depp suggests the following: • Exercise for at least 30 minutes daily  (a simple walk is sufficient). • Strength training two to four times a week, best with alternate days. • Flexibility (stretching before and after exercising). • Practice brain fitness as well as physical (many programs to pick). • Avoid depressing thoughts, situations and people. • Social integration as well as sufficient time spent alone. Another surprising conclusion was that stress, usually considered a negative, can be turned over, like a coin, and used like a mild dose or vaccine to strengthen the system. Muscle training, if done correctly, uses this same principle. The last and possibly the most important element is attitude. With a healthful attitude, the body becomes and stays healthier. Among the increasing numbers of centenarians who are still productive, the one trait they all exhibit is a positive outlook toward most situations. — Mera Kelley is a gerontologist and La Jolla resident.