It’s no secret that the Western diet is loaded with salt. The U.S. Department of Agriculture recommends 3/4 teaspoon of salt each day, but most Americans eat 50% more than that on a daily basis. We know that too much salt is bad for your heart, but now, a study on human and mice cells has found that consuming too much salt can have negative effects on the brain and harm neurons.
Learn more about this study and the effects of a high salt diet on the brain and body.
High Salt Diet Increases Risks for Head and Heart Health
A new study has found that a high salt diet can lead to inflammation, which is linked to all major diseases, including Alzheimer’s disease and dementia. The study from Weill Cornell University, published in Nature Neuroscience, found that when mice were fed a salty diet, they experienced a reduction in blood flow to the brain and an increase in a pro-inflammatory chemical that damages the lining of blood vessels.
There is an immune response to salt that increases the number of immune cells called TH17. TH17 releases a pro-inflammatory chemical called IL-17. IL-17 damages blood vessels and suppresses nitric oxide, which helps blood vessels relax and is necessary to make new memories. In the absence of nitric oxide, neurons struggle to function, leading to behavioral difficulties.
Dr Iadecola, a leading expert on dementia at Weill Cornell University, said, “Normal cognition function requires an adequate, well-regulated delivery of blood flow. Neurons are very finicky, like little children, they only want one kind of food: only glucose and oxygen.” Without enough of those two “foods,” neurons will not function as they should.
Dr Iadecola added that “In aged mice fed a high salt diet, performance at the novel object task was impaired earlier, eight weeks, than in young mice, 12 weeks.” The mice that were fed a high salt diet struggled through spatial memory tests and normal cognitive functioning – including how to build a nest. Dr. Iadecola noted, “Nest building and burrowing are spontaneous rodent behaviors akin to activities of daily living typically altered in patients with cognitive impairment.” He also adds that while this study was conducted on mice, there is evidence that salt affects human cells in the same way.
How Diet and Lifestyle Change Impact Brain Health
As researchers push for a cure for Alzheimer’s and related forms of dementia, the importance of lifestyle choices becomes paramount for prevention. In this case, researchers resumed a normal diet for the mice and after four weeks, brain scans showed healthy blood flow to the brain.
Dr. Sara Imarisio, head of research at Alzheimer’s Research UK says, “This research not only highlights the importance of the immune system for brain health but also suggests that changes in the gut can play a role.”
She continues, “The findings highlight the importance of cutting out the excess salt in our diets, as well as identifying possible new avenues in the search for treatments to help those with memory problems or dementia.”
Have you seen a correlation between a high salt diet and memory loss? Has reducing salt intake helped improve memory in yourself or a loved one? We’d like to hear your experiences in the comments below.