Want to live to be 100 and be happy and healthy while you're doing it? Here are six secret keys to your very own fountain of youth, from researcher Dan Buettner, author of the "The Blue Zones":
Laugh long and often
Not only is it fun, but a good, long giggle relaxes blood vessels and lowers your risk of heart attack.
Nosh on nuts
Studies of a Seventhday Adventist group in California found that those who ate small portions of nuts five days a week lived an average of two years longer than those who didn't.
Cherish your friends
Keep a tight knit circle of close buddies around you visit often and share your innermost hopes and fears. "Gather people around you who will reinforce your lifestyle," advises Buettner.
Okinawas, who boast an unusually high number of healthy seniors over 100, begin every meal by saying, "Hara hachi bu!" The saying translates to "Eat until you're 80% full!" Buettner recommends eating slowly off smaller plates to make smaller meals satisfying.
You don't have to run marathons or schedule gym time. Just make physical activities long walks, puttering in the garden or playing with kids a part of your regular routine.
Live like you mean it
"Across the board, those living the longest had a clear sense of purpose," Buettner explains. "You have to know why you get up every morning." Find ways to connect with things you feel passionate about and get involved.