Chef Alex Guarnaschelli puts her spin on spinach salad by adding sweet candied bacon, salty feta cheese and sautéed fennel.

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Researchers have identified an important link between the consumption of lutein-rich foods and brain health in older adults.

Gillie Houston
December 20, 2016

While most kids are told to eat their spinach and broccoli so they grow up strong, a new study published in the journal Frontiers in Aging Neuroscience suggests that these greens can significantly affect basic brain functions and intelligence later on.

Researchers at the University of Illinois have identified an important link between the consumption of lutein-rich foods and brain health in older adults. Lutein, a plant pigment prevalent in leafy green vegetables, cruciferous vegetables, accumulates in the brain over time, embedding in cell membranes and influencing certain neurological functions.

According to Marta Zamroziewicz, a University of Illinois graduate student who led the study, lutein plays "a neuroprotective role," and can be "linked to cognitive performance across the lifespan." While previous research has shown that lutein gathers in the gray matter of the brain "known to underlie the preservation of cognitive function in healthy brain aging," Zamroziewicz set out to determine the specific cognitive elements most affected by the plant pigment.

A test group of 122 healthy adults aged 65-75 were asked to solve problems and answer questions that reflected "crystallized intelligence," or the ability to effectively use the knowledge and skills acquired over a lifetime. Researchers also collected blood from each participant to test for blood serum levels of lutein, and performed MRI imagery on each of the test subjects' brains to measure for the volumes of various structures.

After evaluating each participant's brain make-up and test results, the researchers determined that adults with higher blood serum levels of lutein performed better on the crystallized intelligence tests. Zamroziewicz noted that while serum levels primarily reflect recent dietary intake, they have also been associated with long-term dietary intake in older adults.

Those with higher lutein levels in their blood also tended to have a greater volume of gray matter in their parahippocampal cortex, a focal region imperative for healthy aging. According to Aron Barbey, Illinois psychology professor and co-lead of the study, the "gray-matter volume of the parahippocampal cortex on the right side of the brain accounts for the relationship between lutein and crystallized intelligence." This new-found data offers "the first clue as to which brain regions specifically play a role in the preservation of crystallized intelligence, and how factors such as diet may contribute to that relationship."

Though Zamroziewicz notes that further testing will be needed to further determine how lutein in the diet specifically affects long-term brain structure, it's clear that an extra helping of kale salad at dinner could pay off big time down the line.