Optimistic women live longer. That’s the conclusion of a new study published in the Journal of the American Geriatrics Society. Harvard researchers collected data from almost 160,000 women from different racial and ethnic groups between the ages of 50 and 79 followed them for up to 26 years. They found that the 25 percent of women who were most optimistic had over a 5 percent longer lifespan. They were 10 percent more likely to live past age 90, compared to the quarter of women who were least optimistic.