Including veggies like spinach and kale can keep your cognitive functions from declining by 11 years.

Rush University in Chicago researchers found that adults who ate the leafy vegetables suffered considerably less cognitive decline than those who didn't, the Independent reported.

The findings were regardless of other factors such as education, exercise and family medical history.

They analyzed 950 people with an average age of 81 years, who participated in 19 different tests to assess their mental function, and found that participants who ate greens once or twice a day halted their mental decline by 11 years.

Lead study author Martha Clare Morris said the brain benefits associated with dark leafy greens likely stemmed from key nutrients such as vitamin K.

She added that since mental decline was linked to Alzheimer's disease and dementias, consumption of green leafy vegetables could be key to protect the brain.

The study was presented at the Experimental Biology Conference in Boston.