A sore throat is one of the most annoying nuisances we can encounter during the day, right up there with an incessantly runny nose or a pounding headache. We’ve been told all our lives that gargling with warm saltwater can help alleviate it, and it’s surprising to discover that this home remedy can actually work! Why is this the case?
It all comes down to osmosis. There are a couple reasons why gargling with saltwater can soothe a sore throat. First, a sore throat can occur due to an overabundance of bad bacteria in the throat. Osmosis is what happens when a solvent moves from an area of higher concentration to an area of lower concentration, which occurs because both sides want to achieve equilibrium. In layman’s terms, the sodium in the saltwater passes through the membranes in your throat, creating a salty environment that’s not hospitable for bacteria.
While saltwater may kill some bacteria, many strains of bacteria are resistant to salt. Thankfully, saltwater draws out the excess fluid that builds up during an infection, called an edema, from your throat, also through osmosis. Drawing the edema out can help reduce swelling and also dehydrate your throat slightly, creating an environment that’s not hospitable for some bacteria. Salt is more soluble in warmer water, which is why warm saltwater is preferred.
If a sore throat doesn’t go away, it can be a sign of strep throat, which needs to be treated with antibiotics. But gargling with warm saltwater every couple hours can definitely alleviate some of the discomfort!