Generally, the reasons for monitoring salt intake are related to cardiovascular health. However, in addition to the risk of high blood pressure, scientists have discovered another factor related to salt, which directly indicates a connection between the gut and the brain.
Back in January, researchers at the Feil Family Brain and Mind Research Institute in New York used mice to track the biochemical pathway responsible for the increased risk of stroke and dementia in people who consumed too much sodium. For several years now, it has been known that a diet high in salt increases the risk of cerebral small vessel disease, a term that encompasses all types of abnormalities associated with deterioration of the capillaries in the brain, which in turn can lead to such diseases. like stroke and dementia. This is due to the fact that the sodium ion "pulls" water into the vascular system, increasing pressure and causing hypertension.
In a new study published in the journal Nature Neuroscience, scientists have attempted to find other links between salt intake and the risk of stroke and dementia. The research team tried to find an alternative explanation as a result of studies suggesting that common table salt can lead to autoimmune diseases, turning certain types of white blood cells into hostile ones. These T lymphocytes release a chemical that promotes inflammation, called interleukin-17, which has piqued the interest of scientists.
By putting the mice on a diet high in salt, the researchers found cognitive impairment and signs of circulatory disorders.
In their experiment, the scientists used both normal mice and those with altered genes: the animals produced interleukin-17 even on a relatively low-salt diet. All of this indicates that a high-salt diet triggers the gut immune system to generate a signal that affects blood vessels in key parts of the brain, namely the hippocampus and cerebral cortex.
It is noteworthy that these violations were recorded even in the absence of high blood pressure. This means that even if we manage to cope with the hypertension that comes from a high sodium diet, the increased risk of stroke and dementia may persist.
But there is one more conclusion that can be drawn from this study: the results obtained made another contribution to the study of the connection between the intestine and the human nervous system. This year alone, research has been conducted uncovering new neural circuits in the gut nerves, the molecular pathways that connect gut microflora and brain cells, and the link between diet and mood swings. All this brings together research linking the composition of microbes in the digestive system with the development of many diseases, such as Parkinson's disease.