While Lumosity may have oversold the merits of its brain-training games, there are still plenty of other ways to keep your mind sharp -- and they don't even require an iPhone.
According to psychiatrist Daniel Amen, body weight plays a big role in brain function. He told HuffPost Live that smart eating habits not only benefit your body, but also fuel your mind.
"You've got to be on the right diet," Amen said. "And the standard American diet, the fast food diet we have, it promotes illness in so many different ways, from Alzheimer's disease to cancer to ADHD."
Amen added that a "brain-healthy diet" should be low on sugar and filled with veggies, clean protein and healthy fat. He also suggested doing 45-minute workouts a multiple times a week and interspersing your regiment with coordination exercises -- like dance or table tennis -- in order to stimulate your brain.
But there's one aspect of the formula that has nothing to do with physical activity or nutrition: Staying engaged with your life and finding purpose.
"People actually live 15 percent longer if they're purposeful, [if] they love their life, [if] they have a reason to get up in the morning," he said.
Watch the full HuffPost Live conversation about keeping your mind agile here.
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