With the average UK adult taking in 1/3 more salt than they need every single day it’s no wonder the government is keen to make us all aware of the health risks of too much sodium. Tales of hardening arteries, high blood pressure, and heart disease might leave you wondering if you’d be better off trying to avoid sodium altogether, but this key ion plays several essential roles in the body and when levels fall too low the results can be deadly.
The role of sodium in regulating blood pressure is well known; when sodium is dissolved in the blood plasma it attracts water to help keep the blood thin enough to easily flow round the body. Too much sodium leads to the blood retaining too much water, which increases the volume of blood in the system and puts extra pressure on the blood vessels. Too little sodium and water starts moving out of the blood plasma and into the cells, while most cells have enough space to accommodate this extra water the cells in the brain don’t. With nowhere to go brain cells are crushed against the skull and, if left untreated, can be permanently damaged.