|March 18, 2022

Just 1-2 Daily Servings of Leafy Greens Slows Cognitive Decline, Study Finds

By Julie Hand
Reviewed by Emily Gonzalez, ND for Scientific Accuracy

Just 1-2 Daily Servings of Leafy Greens Slows Cognitive Decline, Study Finds

A 2018 study[1] published in Neurology demonstrates that a daily dose of leafy greens – think spinach, kale, collard greens, bok choy — is linked to sharper memory and slower cognitive decline in seniors.

Leafy greens consumption slows cognitive decline substantially

To understand the relationship between leafy greens and age-related cognitive changes, 960 seniors with an average age of 81 and no signs of dementia underwent a variety of memory tests, while scientists monitored their eating and lifestyle habits. The people were placed in one of five groups, based upon the amount of greens they consumed. The top group, representing those who ate the most leafy greens, ate an average of 1.3 servings per day. (One serving equals ½ cup of cooked greens or 1 cup of raw greens.) The bottom bracket represented those who ate little to no greens. After five years of observation, the top group’s rate of cognitive decline was half the lowest group’s decline rate.

Past research on vegetables and brain health also supports the latest findings. A 2006 study[2] found that women who ate large quantities of vegetables – specifically, leafy greens and cruciferous veggies, like broccoli and cauliflower – had less cognitive decline.

Vitamin E, vitamin K, lutein, beta carotene and folate are key compounds in leafy greens

The benefits of eating leafy greens come from a few key nutrients, including vitamins E and K, lutein, beta-carotene, and folate. “They have different roles and different biological mechanisms to protect the brain,” says Martha Clare Morris, a professor of nutrition science at Rush Medical College in Chicago. While further research is necessary to understand their precise influence, Morris adds, scientists do know that eating too few of these crucial nutrients is problematic.

Get to know your greens

Dark varieties of lettuce like arugula, escarole, and mâche are high in potassium, carotenoids, vitamin K1, iron, and fiber. However, these lettuces rot easily and mold quickly – so aim to eat them only when fresh and buy organic whenever possible.

Kale, spinach, and chard are all high-nutrient leafy greens, though they should be lightly steamed to minimize oxalates, compounds that bind to calcium in your blood and causes muscle weakness, abdominal pain, and inflammation in sensitive individuals. So always cook these leafy greens, as well as cruciferous veggies like broccoli and cauliflower.

Ways to sneak greens into your diet

Ready to bolster up your intake of greens? Here are some savvy ways to get greener than you ever thought you could.



  • Opt for a collard green wrap instead of bread.
  • Make Hearty Green Soup your main course at lunch.


  • Order a burger on top of your salad, rather than a bun.
  • Try this Paleo Steak Bowl, topped with a full head of bok choy.


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