A lot of kitchen cabinet “cures” parents and grandparents recommend are nothing more than old wives’ tales. no, urinating on a jellyfish sting doesn’t really take the pain away. no, taking vitamin B1 supplements won’t keep mosquitoes at bay. no, putting butter on a burn does not speed healing.

If you’re laid up with a cold or flu, well-meaning relatives often admonish you to gargle with salt water to ease the pain of a sore throat. is that home remedy really worth the effort, or should it be taken with a grain of the white stuff itself?

The Straight Talk It really works. If you have a sore, irritated throat and congestion, gargling with salt water can indeed help ease the pain temporarily. It’s not just the placebo effect at work, either. a sore throat is caused by swollen, inflamed mucous membranes and excess mucus, and gargling can help alleviate both of these symptoms. its primary purpose is to help decrease swelling; among its many other uses, salt is known for drawing out moisture. Gargling with salt water absorbs excess fluid from swollen tissues, which temporarily reduces their size and makes them less painful. It also dries out any lingering bacteria in the throat.

Salt water’s other pain-fighting action is to loosen up the excess mucus that coats the throat during times of sickness. the salt and the gargling action encourage the mucus—along with the bacteria, fungi, allergens, dust, and other particles that could be causing pain and irritation—to break up and flush away.

This simple solution is so powerful, studies suggest that during cold and flu season, prophylactic gargling can even help prevent illness. a study published in the American Journal of Preventive Medicine in 2005 followed test subjects during the winter. Those who were instructed to gargle three times per day, even while healthy, had a nearly 40 percent reduction in upper respiratory tract infections over the control group, who didn’t gargle at all. the gargling may have helped fend off viruses and bacteria by preventing the buildup of mucus for the microbes to take up residence in.