Eating one to two servings of salad with spinach, lettuce and kale daily may keep your brain 11 years younger as well as prevent dementia, according to a study.
The study found that people who ate at least one serving of green, leafy vegetables a day had a slower rate of decline on tests of memory and thinking skills than people who never or rarely ate these vegetables.
In people who ate the most of green, leafy vegetables brain ageing slowed by 11 years.
"Adding a daily serving of green, leafy vegetables to your diet may be a simple way to foster your brain health," said Martha Clare Morris, from the Rush University in Chicago.
"Projections show sharp increases in the percentage of people with dementia as the oldest age groups continue to grow in number, so effective strategies to prevent dementia are critical," Morris added.
The study, published in the journal Neurology, involved 960 people with an average age of 81 who did not have dementia and were followed for an average of 4.7 years.
Over 10 years of follow-up, the rate of decline for those who ate the most leafy greens was slower by 0.05 standardised units per year than the rate for those who ate the least leafy greens. This difference was equivalent to being 11 years younger in age.
The results remained valid after accounting for other factors that could affect brain health such as smoking, high blood pressure, obesity, education level and amount of physical and cognitive activities, the researchers said.