Potassium and Sodium form another electrolyte pair that relate to each other and face connected problems when affected by kidney disease. First of all, these two chemicals form a specific balance of fluids inside and outside of the cells of the body. Potassium is highly concentrated inside cells, while sodium is more highly concentrated outside.
While sodium regulates fluid levels throughout the body itself, the sodium-potassium inside-outside chemical balance of the cells is very important. This balance creates an electrically charged potential at the cell membrane. And it’s this electrical potential that is crucial to such things as heart function, muscle contraction, and the transmission of nerve impulses. If these chemicals are thrown out of balance, it’s clear that people could suffer anything from heart problems to weak muscles or even nerve problems.
The kidneys serve a vital function in keeping these electrolytes balanced, excreting excess amounts so the body stays regulated. But what happens if there is more of a particular chemical in the body than the kidney can possibly eliminate? We see this question coming more and more to the forefront as the North American diet, in particular, is increasingly swamped with sodium. Excess sodium can lead to fluid retention, high blood pressure, and kidneys that become so overworked that they start to falter or even fail.
At the same time, if the kidneys aren’t able to function at full strength, and can no longer eliminate potassium in the way they are supposed to, people can begin to experience a condition known as hyperkalemia. This promotes further buildup of fluid in the body, but its worst effects have to do with the heart. It may result in a weak or irregular heartbeat, and a difficulty controlling the muscles. At its worst, it can lead to problems with breathing, weakness, or cardiac arrest. But like so many conditions related to kidney function, it often shows no symptoms at all until the kidneys are already severely compromised.
Doctors need to be careful in trying to rebalance sodium and potassium. When patients receive diuretics that promote urination, to remove excess sodium, they sometimes experience depleted potassium, which creates further nerve, heart, and muscle problems. Yet a lack of balance can damage the kidneys – and damaged kidneys can throw the balance even further out. It’s far better to eat a healthy diet and promote kidney health to begin with, than scramble to try to fix these electrolyte imbalances after they arise.