Shake N’ Shake-Salt
By Dr. John A. Lopes Ph.D.
Are you a salt everything or a salt minimalist? Besides taste salt is an important component of healthy life. Both animals and plants require salt for wellbeing. An elephant matriarch leads the herd several miles to get salt in their diet. Cockatiels fly hundreds of miles to distant salty mountain peaks to get their salt complement.
Camel caravans traveled to distant places to trade salt a valuable commodity. Mahatma Gandhi initiated passive resistance to the unjust tax for making salt from sea water to start to get freedom from British rule.
Recently fast food giants amassed wealth by increasing profit margin with cheaper products high in salt to customers. Besides diet salt has also been used since millennium as a food preservative to prevent spoilage by microorganisms, for pickles, meat, and fish. However, there is a recent trend to overuse salt in fast food either for enhanced taste or to extract more profit by increasing weight of products.
Excess salt in fast food has become a norm. People are always in hurry. It is difficult to get low salt foods such as hamburgers, french fries, ham sandwiches hot dogs, pizza and more fast food items. Even in regular sit-down restaurants it is difficult to get a low salt meal.
Although, recent findings suggest that high salt may not be the only cause of high blood pressure, stroke and declining cognition and memories. Dr. Costantino Ladecola and a team of researchers at Weill Cornell Medicine found that mice fed with high salt diets had trouble recognizing novel objects and navigating through a maze. They related high salt diet to the reduced level of enzyme that produces NO (nitric oxide). Nitric oxide helps blood vessels to relax resulting increased blood flow. The mice on the high salt diet had reduced blood flow to the brain resulting in poorer performance on a standard set of cognitive tasks.
Further investigations by the researches showed that only reduced blood flow to the brain did not entirely explain reduced cognition in the mice. It has been known that a protein called TAU accumulates in the brains of people with Alzheimer’s disease. The research team found that a high salt diet reduces the level of nitric oxide which indirectly results in adding phosphate groups (phosphorylation) to TAU. When phosphorylated TAU protein clumps together in the brains. Clumps of tau are linked with some dementias, such as Alzheimer’s disease.
Further molecular studies showed that the effects of high salt on the phosphorylation of the protein tau were mediated through nitic oxide levels, and not through the reduction in blood flow. The scientists found that reduced thinking and memory function was directly related to lower nitic oxide level. After being placed on a high salt diet for 12 to 36 weeks the mice were tested for cognitive functions and their brains were examined for molecular changes.
Previous study by the team has shown that even with high salt diets mice, fed with a compound that increases production of nitric oxide, can overcome the accumulation of phosphorylation of tau. Further studies with mice which lacked TAU had no deleterious effect to cognitive tasks with high salt diet.