Why are sodium and other electrolytes important for worker health and hydration?

In the conversation about hydration, the term "electrolyte" comes up often. It’s common knowledge that water is the key to proper hydration – so why not just drink water? In most cases, you can. However, when exercising, working in the heat, or battling dehydration, more may be needed to bring the body’s chemistry back into working balance. This is where supplementing electrolytes may come into the picture.

(Learn more in A Sweaty Situation: PPE, Hydration, and How to Manage Both.)

What are electrolytes anyway, and why do we need them? Water itself, contrary to conventional assumption, does not conduct electricity. It is a dissolving medium, but needs to contain conductive ions to actually move an electrical current. This is in the form of dissolved mineral “salts” (sodium, potassium, chloride, calcium, and bicarbonate) which serve as electrolytes and allow for flow of electricity.

The nervous system relies on a balance of potassium and sodium (positive ions, or “cations”) inside and outside of cells to transmit signals throughout their circuitry. Depletion of those ions means that the nervous system may be impaired, but it isn’t the only system affected.

(Find out What the Latest Research Tells Us About Hydration.)

Somewhat counter-intuitively, drinking too much plain water can actually exacerbate the imbalanced condition and lead to a state called hyponatremia – a balance of sodium that is too low. When too much water is added to the solution it becomes dilute, and the concentration of sodium per unit volume goes down. Hypokalemia is the name given to the corresponding drop in concentration of potassium ions.

Sweating will decrease the levels of both water and salts, but should do so in a relatively balanced way. Even with normal sweating, about 220mg of sodium and 63mg of potassium are lost for every 315mL of sweat. In this kind of dehydration, a drink packed with electrolytes might fit the bill, but it isn’t the only type of water loss.

When body water decreases but salts are retained (as with blood loss or diarrhea), hypernatremia (excess sodium) or hyperkalemia (excess potassium) may occur. In extreme cases, this can lead to kidney failure or cardiac arrest. In this case, supplementation of electrolytes would certainly be unnecessary!

Maintaining the balance of water and electrolytes in the body is crucial, especially for those working in hot environments. Proper intake of water can help make sure things stay in balance, and if there is excessive sweating, a specialized beverage rich in electrolytes can be a good supplement.