Study finds racism causes Black Americans' brains to age faster than people of other races — increasing dementia risk

• A study of brain scans of Black, White and Latinx people found Black brains age faster than other races.
• The study found Black brains exhibited signs of aging like greater white matter sooner than other brains.

Black brains age quicker than white brains, and racism might be why, according to a new study.

A new study, published in JAMA Neurology on Monday, analyzed the brain scans of 455 Black participants, 275 white participants, and 737 Latinx participants.

Researchers found brain scans of middle-aged and elderly Black participants had more signs of cerebrovascular disease, or disorders that effect blood supply to the brain and that are common among people with Alzheimer's, than white brains of the same age.

Black brains also exhibited signs of aging sooner — at around mid-life — compared to white and Latinx brains. These signs include how much white matter is in the brain and the width of gray matter in the outer layer of the brain.

The paper suggest the "cumulative effects of oppression, environmental adversity, and psychological stress" — or a lifetime of exposure to racism and discrimination — might be causing Black brain to age faster, since scientists have previously determined these factors can lead to cognitive decline.

Scientists have linked racism and discrimination to a variety of worse health outcomes for Black people, including higher infant and maternal mortality rates, shorter life expectancy, and more heart problems.

Now, researchers are better understanding how racism can harm the brain. A previous study that collected data from 59,000 Black women found those who experienced daily microaggressions and systemic discrimination were 2.75 times more likely to have worse cognitive functioning, an earlier indicator for Alzheimer's disease.

Alzheimer's is a progressive brain disorder that slowly weakens memory and other mental functions. Older Black Americans are twice as likely as their white peers to have Alzheimer's or dementia, and many of them do not get diagnosed until the disease process was more advanced, per the National Institute on Aging.

Adam Brickman, a professor of neuropsychology at Columbia University and the study's main author, told STAT he was surprised to see brain aging begin so quickly in Black people. The authors of the study did not respond to Insider's request for additional comment.

"It's evidence that when we think about outcomes in late life, a lot of those changes are starting earlier in life," Brickman told STAT. "Cognitive aging is a lifelong phenomenon, not just something that happens when you turn 65."