It's always a good time to support your brain longevity (aka brain span), but if any decade is the pivotal moment to lean into habits that promote cognitive health and function, it's your 40s. After decades of monumental life transitions through your 20s and 30s (College! Starting a career! Getting married!), chances are you've slowed down (or at least settled down) a bit during this phase of your life.
Maybe you have children and find your day filled with the typical familial routine—drop the kids off at school, take care of loads of errands and chores, pick the kids up from soccer practice, whip up a quick dinner, head to bed, repeat. Or perhaps your day is filled with business to-do's, like a hard day's work at the office or running your own company. Maybe your day is even a combination of those two scenarios (or none of the above). No matter where you are in life, it's important that your brain can keep up.