We all know that excess salt is bad for the heart. Now researchers at Weill Cornell Medicine in New York City suggest that too much salt in the long run can hinder a person’s ability to think. The resulting study, published in the journal Nature, linked high-salt diets to cognitive impairment in mice.
Their work showed that in mice, the salt lowers nitric oxide levels in the brain’s blood vessels. This decrease produces a rise in certain enzymes that alter important proteins in neurons, which then hinders neuronal pathways involved in cognition. In lab animals, a brain change happened in two months. The change also shows an accumulation of tau deposits, or fully saturated proteins, that presage Alzheimer’s disease.
Neuroscientist Costantino Iadecola says humans would notice poorer cognition after several years on a high-salt diet. But there is good news for those who have overdone the salt: “Going back to a regular diet completely reverses the cognitive deficits,” Iadecola says.
In a press release from Weill Cornell Medicine, he also made clear where the most dangerous salt comes from. “The stuff that is bad for us doesn’t come from a saltshaker, it comes from processed food and restaurant food… We’ve got to keep salt in check. It can alter the blood vessels of the brain and do so in [a] vicious way.”