Researchers followed more than 1,200 older Australians with normal memory and cognitive function over a six-year period.
Participants answered questions about their diet and completed tests of memory, attention, language, and other cognitive abilities every 18 months.
The study was published in the journal Neurobiology of Aging and was reported by Prevention.
Indirect effects on the brain
A high salt intake is already known to increase the risk of high blood pressure.
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According to dietitians Jennifer Pallian and Lauri Wright, it can damage blood vessels and increase inflammation in the body, Prevention reports.
Over time, this may affect brain function and memory.
Neurologist Alexander Zubkov also told Prevention that consuming too much sodium may reduce blood flow to areas of the brain that are important for memory.
The World Health Organization recommends that adults consume less than 2,000 milligrams of sodium per day.
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One group stood out
The researchers did not find a clear link between high salt intake and poorer cognitive abilities across all participants.
However, when they analyzed men and women separately, a difference emerged.
Older men with a high salt intake experienced a greater decline in episodic memory, which is the ability to remember personally experienced events.
According to the researchers, the study cannot prove that salt is the cause because it is an observational study.
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However, the findings support existing evidence suggesting that a high salt intake may affect brain health over time.
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