Eighty-five years ago, researchers at Harvard embarked on a decades-long study to figure out what really drives happiness, health and longevity.

• The results are in.

🖼️ The big picture: It's close relationships with family and friends — not wealth, exercise or success at work — that bring us the most joy and even lengthen our lives.

• Fun fact: When the Harvard study began in 1938, researchers selected 724 young people to follow throughout their lives. That group included former President John F. Kennedy, Harvard notes.

⚡ Flashback: As we've reported, Americans value family and work — but friendship often falls behind. Many of us have few or no close confidants.

• On top of that, there's a growing group of Americans who are aging without a spouse or a partner, any children or siblings.

What to do: Think about improving your "social fitness," CNBC reports.

• It's not enough to just let romantic and familial relationships or friendships develop on their own. These need care, attention and exercise.

Here are three tips, from earlier Finish Lines:

1. ☎️ Check in. We way underestimate how much the simplest text or call means to our friends, family members and colleagues.
2. ⏳ Find the hours. It takes about 90 hours to advance from casual pals to good friends, and it takes more than 200 hours to become confidants, research shows.
3. 🔙 Go back in time. Our anxiety can prevent us from reaching back out to an old friend with whom we've lost touch. But reviving those dormant ties can do us a lot of good.

Enjoy this other-worldly snap from reader Frederick L., who writes: "I took this recent photo of the bay in Santa Clara County, California, as my flight was landing at the San Jose airport."