If you could travel back in time and give your younger self some advice, what would you say? New research suggests mulling over this question is a very common human experience.

Robin Kowalski was so “laser-focused on school” as a teen that she’d tell herself to lighten up a bit and enjoy life more.

“I would have stopped to smell the roses, and that’s a message I shared with my own children,” Kowalski, 55, a psychology professor at Clemson University in South Carolina, told TODAY.

Kowalski is the lead author of the first study to look at what kind of advice people would offer to their younger selves if they could.

It turns out we think about this stuff a lot, with a third of adults pondering the subject “spontaneously” at least once a week. The experience can also be therapeutic: The Child Mind Institute in New York City has a #MyYoungerSelf campaign inviting people who grew up with a mental health disorder to share messages of hope.

Even Oprah Winfrey, 65, thinks about what she’d say: She’d tell her younger self to “relax, stop being afraid” and to believe “everything is going to be alright.”

The average age of the younger self people in the study talked to was 18. The findings, published in The Journal of Social Psychology, are based on responses from more than 400 participants who were 30 or older.

Across two surveys, the top three areas the advice focused on were:

Relationships:

Sample responses included:

• “Don’t marry her. Do. Not. Marry. Her.” (This was Kowalski’s favorite response.)
• “Don’t have sex with men until you know them well.”
• “Don’t lose hope in finding someone for you — she is out there.”

Many of the entries also included poignant reminders to take advantage of time with loved ones who have passed away.

Education:

Respondents would tell their younger selves:

• “Stay in school. Don’t drop college no matter how many promotions you get.”
• “Get master’s while in your 20s.”
• “Finish college in four years.”

Advice in this category was often tinged with regret, Kowalski said. “But education is an interesting thing because depending on age and financial ability, you can go back and fix that,” she noted.

Taking care of yourself:

Many people have trouble being kind to themselves, Kowalski said, so this is what they’d tell their younger versions with hindsight:

• “Be kinder to yourself.”
• “Always know your worth.”
• “The world is bigger than you think it is and your worries aren’t as important as you think they are, just be you.”
• “Don’t worry if you look different, or feel you look different, from most other people. There is much more to you than what others see on the surface.”
• “Don’t get so caught up in the difficulties of the moment since they are only temporary.”
• “Don’t dwell on the past. Just because it was that way doesn’t mean it will be that way again.”

For many people, the advice is still valid today

The study participants said following those tips would bring them closer to their “ideal self” — the part of a person that focuses on hopes, goals, aspirations and dreams.

In most cases, the advice was inspired by a pivotal event that happened in people’s lives between the ages of 10 and 30, the study found. That included events like meeting a life partner, watching parents go through a divorce, dealing with health problems or experiencing a death in the family.

Some of the advice dealt with experiences that people couldn’t change. The person who yearned to tell her younger herself, “Don’t have a child at 16,” for example, obviously could never undo becoming a teenage parent.

But other advice people would give their younger selves still applied today. In fact, almost two-thirds of the respondents said they have followed their own tips.

“That fascinated me,” Kowalski said. “Following the advice takes effort… (but) if people could take the advice that they have to offer, I think it would really make a difference.”

And remember, if looking back fills you with regret, realize you did the best you could at the time, experts said. Happy adults view their younger selves with compassion, and use regret to motivate change, the study noted.