…eat plenty of broccoli and onions. A study in the journal Genesis found 3 cups of cruciferous vegetables a week led to less brain fog and better decision-making and helped the brain function as if it were 6 years younger! It’s down to a compound called sulforaphane, which works to repair and replace aging neurons. You just need 3 cups of cruciferous vegetables a week, like broccoli, cauliflower, or cabbage. And add a quarter cup of onions to your daily diet to help the liver flush away toxins, which can slow brain aging by 21%.