Even in old age, the visual evidence shows that we should change our minds, change our thinking.

Take it from me if you aren’t there yet, when you’re a grandfather it all comes back to you: how beautiful are the happy smiles of infants and little kids. You see them with Mom or Dad walking on the sidewalk or in the store, and they bring smiles to your own face.

Their reaction to you may be somewhat the opposite, as they gaze up upon a face that is old, wrinkled, sagging and eternally grumpy. The youths’ cute smiling faces may become a bit confused, twisting their smiles into doubts and dismissals.

In ostensibly unrelated circumstances, the tabloids are forever exposing the bloated close-ups of celebrities revealed as creatures overstuffed with botoxins to erase their own wrinkles of age and stress. You might think these are sad examples of bad plastic surgery gone way too far.

May I take this occasion to disagree. Rather I would perhaps superciliously argue these fluffed-up illustrations of the potential for change simply do not go far enough — not only in the blown-up stuff, but also in terms of a new market opportunity targeting the elderly (Hey, I’ll soon be there myself… or maybe I am already).

When observing their grandparents or other old people of similar vintage, what would make little kids smile? How about old folks who look just like them: their heads more roundish, their cheeks pillow-puffier, arms and legs inflated, with big wide grins right above their soft chins?

Now is the time I might suggest that this much-older-to-much-younger extreme makeover become a new model for baby-faced senior citizens in the Land of the Free (and at affordable cost in their waning years). Here is my strategic roadmap for senior beauty:

• Eat more as you get older, growing a natural chubby belly on your own.

• Get lots of plastic surgery and botoxin injections to fill out your face and your figure.

• Also inject lips with lots of that plastic or whatever, then sew each corner winding up toward the ears for an everlasting smile.

• Paste wigs on bald heads — no white hair, though sparse hair of light colors might look best to younger eyes.

• No glasses, no need to see beyond a few feet from a kid’s face, though sprinkle glitter in the pupils to enable twinkling eyes day and night.

• Insert earplugs so elders constantly hear little kids laughing all the time.

You will laugh, and they will laugh. To them you’ll look just like they do, only bigger, though also perhaps not quite yet able to walk, like some of them.

For those seniors who may have difficulty walking anywhere and everywhere on their own, scooters may be upgraded to make them look more like baby buggies.

And whenever you run into little kids a the grocery store, just give them a giggle, and they’ll see in an instant that you are just like them.

Think young… all over again.