People have an almost universal desire to not only live longer, but to have the years they add to their lives be healthy, vibrant, and fulfilling. 

A big part of making that happen is maintaining your physical fitness, particularly your strength. Muscle loss is a significant driver in decreasing life quality as you age. If you can’t pick heavy things off the floor, or get yourself off the floor, your ability to navigate life diminishes, and along with it, your sense of agency. Solution: keep on lifting heavy things and eating plenty of protein even as you get older. 

Of course, having a fulfilling winter season of life is premised not only on your body staying fit, but on your mind staying sharp. You can’t enjoy being physically spry, if you’ve lost your marbles. Unfortunately, just as your muscle mass declines with age, so does your cognitive function. Fluid intelligence goes down, hampering your ability to think and improvise on the fly, and your memory gets rusty. Age-related cognitive impairment can be mild, wherein you simply lose your keys and forget names more often, or it can be severe, in the form of dementia, which can cause, in addition to serious memory loss, debilitating issues around communication, thinking, and behavior which rob an individual of the ability to perform everyday tasks. 

While not all forms of dementia can be prevented, the solution to those that can, as well as to garden variety age-related mental decline, is much the same as the solution to age-related physical atrophy: exercise. Cognitive exercise. The mind is much like a muscle: you either use it or lose it. 

In response to this recommendation, companies have popped up selling older people programs and apps that promise to exercise the brain in ways that will stave off cognitive deterioration. Just play a fun brain game for 15 minutes a day, they say, and you can stay mentally fit as you get older. 

But the research doesn’t back up the claims of these brain-training companies. Instead of increasing overall cognition, playing these games just makes you better at those games. There’s no transfer to the real world.

So what does work in keeping you mentally sharp as you age?

According to cognitive scientists, the answer is simple: taking part in complex activities. 

There are two such activities you can do that are 1) free, 2) enjoyable in and of themselves, and 3) disportionately effective in keeping your brain tuned-up: socializing with others and physically engaging in diverse environments.

Below we’ll unpack why you should prioritize these activities in your life — not waiting ‘til you’re a senior citizen to start, but beginning in your thirties (or earlier!); it’s easier to keep your mind fit all along and maintain established habits from youth to old age, than it is to reverse decades of degeneration and have to form new habits in your twilight years. (Though it’s certainly never too late to start!)

1. Engage in Face-to-Face Conversations

In our podcast interview with neuroscientist Daniel Levitin about his book Successful Aging, he highlighted research that social engagement helps maintain brain function and protects against cognitive decline as you get older. For example, individuals who keep working into their 70s and 80s tend to have less dementia than people who retire in their 70s. Older individuals who volunteer show similar cognitive benefits. 

What is it about socializing with other humans, particularly face-to-face, that helps keep you mentally sharp?

As Levitin explained, “interacting with others is about the most complex human activity we can do. It’s more complex than brain surgery, than being a rocket scientist, than solving Sudoku or crossword puzzles. Interacting in a meaningful way with real live people, not necessarily over the phone or Skype, that’s demanding, and that keeps the brain active.”

Think about all the nuances and uncertainties, as well as the skills and aptitudes, that are involved in having a conversation: you have to listen, focus, remember what’s already been said, read emotions, empathize, give appropriate responses on the fly, and check your inappropriate responses. You have to stay on your mental toes; it’s a delicate and deft dance that maintains your