One of the cutting-edge topics of medicine is how people can live longer. The chances of reaching the century milestone have never been greater.

So what’s the best way to live longer? Eat “Mediterranean?” Run three marathons a year? Sleep longer?

It appears that standard answers don’t come close. The one that works best is the cheapest and simplest.

Your mother knew it. When you contorted your face into a frown, she might say, “you don’t want your face to freeze like that, do you?”

If you want to live longer, smile.

In a 2010 study, researchers examined Major League baseball card photos from 1952. They found that the span of a player’s smile actually predicted his lifespan–unsmiling players lived 72.9 years on average. Those with wide grins outlasted their peers by 7 years.

The sad truth (no pun intended) is many people don’t smile. Once grown, less than half the adult population smiles more than 20 times a day. It is children who experience joy who smile over 400 times per day.

No wonder Solomon knew what it has taken us centuries to rediscover.

“A cheerful heart is good medicine, but a crushed spirit dries up the bones.” (Proverbs 17:22)

For Christians, reasons multiply to smile. We love others, and God loves us. We have a destiny that eclipses this earth, and our lives have a grander purpose than grinding out the days.

So, let me ask you. Are you smiling? Why not?

-Robert G. Taylor-