Health scare of the week
How salt hurts the brain
A high-salt diet can lead to significant mental decline, according to new research. Scientists at Weill Cornell Medicine in New York City fed mice eight to 16 times their normal salt intake and within eight weeks observed a dramatic drop in blood flow to the cortex and hippocampus, two regions of the brain associated with memory and learning. After three months, the mice were suffering from cognitive decline and struggled to navigate a maze and respond normally to stimulation. High-salt diets are known to increase blood pressure, impairing the flow of blood to the brain. But even mice with normal blood pressure experienced these changes in brain function, said the Los Angeles Times. Upon closer examination, the researchers found excessive salt intake triggered an immune response in the rodents’ small intestine, which increased levels of the pro-inflammatory protein interleukin-17. That in turn impaired the function of blood vessels in the mice’s brains. The researchers believe their findings likely apply to people as well. But the harmful effects of salt can be reversed: The brain function of the mice was restored when they resumed a normal diet.