Packing your diet with certain fruits and vegetables can keep your cognitive health in check as you get older.

When Vincent (Tom Cruise) learns to hustle pool from the old-time pool shark Eddie (Paul Newman) in The Color of Money, he’s taught to go for the green: Eddie: “You smell what I smell?” Vincent: “Smoke?” Eddie: “No, green. Money.”

But later, Vincent discovers he prefers to win on talent instead of trickery. The reformed Vincent wants his green to be good for body and soul, not just the wallet.

Smart choice, say Harvard researchers. They followed 27,842 men, average age 51, for 20 years to see if their consumption of greens, dark red and orange veggies and fruits affected their brain power as they grew older. Every four years, the researchers had them fill out a questionnaire about how many servings of various foods they ate. They also took “thinking tests” when their average age was 73.

Turns out men who ate the most vegetables were 34 percent less likely to develop cognition problems than men who consumed the least amount. And guys who drank orange juice daily (choose the one with pulp) were 47 percent less likely to develop poor thinking skills than the men who drank less than one serving per month.

And having a diet loaded with fruits and veggies when you’re young—that holds up over time, even if you eat fewer of them as you age. In this study, those guys were also less likely to develop thinking and memory problems.

So put the color of money (greens, that is) where your mouth is! You’ll protect your brain power as you age.