But getting proper nutrition isn't the only way to ensure brain health. "I would say that the No. 1 intervention is probably physical exercise," Wint said.

"Every physician wants you to exercise, but from a brain health perspective we know there are small molecules that help improve brain health," Liu noted. "Specifically, there's a growth factor that's released when we exercise, and there's another small molecule that's released that helps people concentrate or focus even more." This could be why you have an easier time focusing on work after going on a lunchtime walk or finishing a morning yoga class.