A recent study finds that consuming one fresh avocado per day improves cognitive function in healthy adults. This is related to the increased levels of lutein in the brain and the eyes.
‘Monounsaturated fats, fiber, lutein and other bioactive compounds make avocados particularly effective at enriching neural lutein levels in the eyes and the brain.’
Forty healthy adults aged 50 were recruited for the study. They incorporated one medium avocado into their daily diet for 6 months. The research team monitored gradual growth in the amount of lutein in their eyes and progressive improvement in cognition skills as measured by tests designed to evaluate memory, processing speed and attention levels.
The control diet included either one medium potato, or one cup of chickpeas in place of the avocado. Chickpeas and potatoes were used as the control diet because they provided a similar level of calories, but a negligible amount of lutein and monounsaturated fats.
They found that after six months there was an increase in lutein levels by 25% in the eyes and improved working memory and problem-solving skills in those who ate avocados. The control group which did not eat avocados experienced fewer improvements in cognitive health during the study period.
One avocado contains 369 mcg lutein. Lutein is a carotenoid, or pigment, commonly found in fruits and vegetables that accumulates in the blood, eye and brain and may act as an anti-inflammatory agent and antioxidant.
"The results of this study suggest that the monounsaturated fats, fiber, lutein and other bioactives make avocados particularly effective at enriching neural lutein levels, which may provide benefits for not only eye health, but for brain health," said Elizabeth Johnson, Ph.D., lead investigator of the study from the Jean Mayer USDA Human Nutrition Research Center on Aging, at Tufts University.
Results of the study reveal that lutein levels in the eye increased with the intake of fresh avocados and the effect was better compared to a supplement. A balanced diet that includes fresh avocados may be an effective strategy for cognitive health, the authors write.
The authors point out that further research is needed to determine whether the results could be replicated if the serving is reduced to 1/3 of an avocado per day (136 mcg lutein).
"While the conclusions drawn are from a single study that cannot be generalized to all populations, the study's outcome helps to reinforce and advance the body of published research on avocado benefits and their role in everyday healthy living," said Nikki Ford, Ph.D., Director of Nutrition of the Hass Avocado Board.
Goodness of the Butter fruit
- Avocado intake increases the nutrient absorption of the food that is eaten along with it.
- Avocados are excellent source of carotenoids, which help to keep your eyes healthy. Every time you consume avocados, you provide good amounts of Vitamin A to your body and thereby protecting your eyes.
- Avocados are rich in beta-sitosterol. This compound has been shown to be effective in lowering blood cholesterol levels.
- The unique combination of Vitamins C and E, carotenoids, selenium, zinc, phytosterols and omega-3 fatty acids help to guard against inflammation and hence prevent osteo- and rheumatoid arthritis.
- Oleic acid, the primary fatty acid generally present in avocados protects the heart.
- Elizabeth J. Johnson et al., Avocado Consumption Increases Macular Pigment Density in Older Adults: A Randomized, Controlled Trial, Nutrients (2017)