Editor's note: Karl A. Pillemer, Ph.D., is a professor of human development at Cornell University and professor of gerontology in medicine at Weill Cornell Medical College. He is also the author of "30 Lessons for Living: Tried and True Advice from the Wisest Americans."
(CNN) -- In an episode of the popular sitcom "30 Rock," television CEO Jack has a hallucinatory encounter with his future self, from whom he receives life advice that helps him avoid major mistakes.
Most of us would also like to know which choices and decisions we make as young people will benefit us later on -- or come back to haunt us. Although there's no way to step into our own futures, we can get a very good sense of what mistakes younger folks should avoid. We can ask our "future selves": our elders.
Based on this premise, over the past six years, I've conducted several studies involving 1,200 older Americans regarding the advice they would offer to members of the younger generation. The research has included a national, random-sample survey, as well as in-depth interviews with several hundred persons identified as "wise." To protect respondents' identities, actual names are not used in the study. Participants ranged in age from age 60 to 108 (average age was 74) and represented a geographically and economically diverse sample of the older population.
The surveys addressed the question, what mistakes should younger people avoid? Respondents were also asked their views on what people are most likely to regret when they get to the end of life.
Answers were categorized into major themes regarding mistakes and possible regrets. The findings reveal some interesting cautions for the young (and not so young as well).
According to America's elders, here are some of the biggest mistakes young people make:
1. Putting too high a priority on money. These elders were affected by the Great Depression, so I thought they might suggest pursuing financial security at all costs. Not so: Their responses were much more like this one from a 76-year-old: "Don't make money number one for everything. You need money, and that's fine, but it can't be your be-all and your end-all. You've got to spend time with your family and not spend every hour on the job and never be home." Most of the elders believe that a fulfilling job trumps a higher-paying but unsatisfying one any day.
2. Getting into debt. These are folks who have lived through economic hardship so tough that it makes what we're experiencing look like a minor blip. So listen to them when they point out the dangers of going into serious debt. From an 89-year-old: "They should avoid spending money they don't have. They should not be using that credit card if they can't make the payment on a monthly basis. That's just my old-fashioned way of doing it. We have a credit card, just one, that we use, and we pay it every month so the following month I don't have a debt that I have to pay from the month before. I wish they would wait until they can afford to buy something before they buy it, because that's why life is so difficult for them."
3. Worrying too much. A little surprising, right? But if there's one do-over the elders wish they could have, it would be not spending precious time worrying obsessively about the future. They said this as clearly as can be: "Worry wastes your life." "Worrying never solved anything. So don't."
4. Excessive drinking and drugs. Okay, we expected that one. This 84-year-old was typical: "For one thing, stay away from smoking; stay away from drugs; stay away from too much alcohol." But believe me, these people know from experience. This advice comes from watching plenty of ruined lives -- and in some cases personal experience. They don't ask you to be a puritan, just to know what moderation is and practice it.
5. Rushing into marriage before you're ready. Nope, they don't want everyone to get married as early as possible. Just the opposite: They want young people to wait until they are really sure (actually, really, really, really sure). And no one was more vehement about this than those who had one marriage fail and a second one succeed. As a 93-year-old put it: "Well, nowadays there are so many divorces, and I think they should be more careful about their decisions to get married. I mean, they should think at the beginning, is this going to be for a lifetime?"
6. Passing up opportunities. The elders much more strongly regret things they didn't do than what they did. As a 73-year-old told me: "The lesson I learned is that it really pays to say yes unless you've got a really solid reason to say no. Life is an adventure, but to take advantage of it, you have to say yes to things."
New Year's Day is fast approaching, and many of us will be talking to our older family members to wish them a happy new year. Why not ask them about the secrets to living a life without regrets? It could make for a very interesting conversation.