Plain, non-iodized salt is the best choice for a mouth rinse. Regular table salt works fine as long as it doesn’t contain additives like anti-caking agents or iodine, which can irritate soft tissues in your mouth. A half teaspoon dissolved in one cup of warm water gives you an effective rinse for most purposes.
Best Salt Types for a Mouth Rinse
You have a few options, and the main thing that matters is purity. Any salt will create the same saline effect, but additives are what separate a comfortable rinse from one that stings or irritates your gums.
- Non-iodized table salt is the most accessible option. Check the label for anti-caking agents like calcium silicate or sodium ferrocyanide. If those are listed, it’s not ideal, though many people use regular table salt without issues.
- Sea salt works well because of its relatively natural composition. Just make sure it’s pure and doesn’t contain added anti-caking agents. Fine-grain sea salt dissolves faster than coarse varieties.
- Kosher salt is another good choice since it typically has no additives. Its larger crystals take a bit longer to dissolve, so stir thoroughly.
- Pickling salt or canning salt is pure sodium chloride with no additives at all, making it a reliable pick if you have it on hand.
Iodized salt is the one type generally worth avoiding. The added iodine and other substances can irritate sensitive oral tissues, especially if you’re rinsing after surgery or around an open wound. Non-iodized alternatives are a safer bet.
The Standard Salt Water Rinse Recipe
The most widely recommended ratio is half a teaspoon of salt in one cup (8 ounces) of warm water. This creates a mild saline solution that’s comfortable to swish without burning. For sore throat gargling, the CDC recommends a slightly stronger mix of one teaspoon per cup of warm water.
Warm water matters for two reasons: it dissolves the salt completely, and it feels more soothing on irritated tissue. You don’t need it hot. Lukewarm, around the temperature of a warm bath, is plenty. Water that’s too hot can injure already sensitive gums or an extraction site.
Stir until the salt fully dissolves. Undissolved grains sitting against a wound or sore can cause unnecessary irritation.
Why Salt Water Rinses Work
Salt water kills many types of oral bacteria through osmosis. The high salt concentration outside the bacterial cells draws water out of them, effectively dehydrating and destroying them. This same osmotic action pulls excess fluid out of swollen, infected gum tissue, which is why a rinse can noticeably reduce inflammation around a sore or surgical site.
There’s also clinical evidence that gargling with salt water helps during upper respiratory infections. A randomized trial published in the Journal of Global Health found that participants who gargled and rinsed with saline during a COVID-19 infection had significantly lower hospitalization rates (around 18 to 21%) compared to a reference group that didn’t rinse (58.8%). Low-concentration and high-concentration saline solutions performed equally well, and earlier research on other coronaviruses found that saline gargling shortened cold symptoms by an average of two and a half days.
Adding Baking Soda
Some dentists recommend adding baking soda (sodium bicarbonate) to your salt rinse, particularly if you’re dealing with acid reflux, frequent heartburn, or chemotherapy-related mouth sores. Baking soda doesn’t kill bacteria directly, but it raises the pH in your mouth, neutralizing acids that erode enamel and creating an environment less friendly to acid-producing bacteria.
A study in the National Journal of Maxillofacial Surgery confirmed that baking soda rinses increase salivary pH above the threshold needed to prevent enamel breakdown and promote remineralization. To add it, use about half a teaspoon of baking soda along with your half teaspoon of salt in one cup of warm water.
Water Quality Matters
For a mouth rinse that you swish and spit, regular tap water is generally acceptable since the solution isn’t entering your nasal passages or staying in your body. However, if you’re rinsing a fresh surgical wound or also using the solution as a nasal rinse, the FDA recommends using only distilled, sterile, or previously boiled water. Tap water can contain low levels of bacteria and amoebas that are harmless when swallowed (stomach acid kills them) but dangerous when introduced into nasal passages or deep wounds.
If you boil tap water, let it roll for 3 to 5 minutes, then cool it to lukewarm before mixing in salt. Boiled water should be used within 24 hours and stored in a clean, closed container.
Timing After a Tooth Extraction
If you’re rinsing after having a tooth pulled, do not rinse your mouth at all for the first 24 hours. Swishing too soon can dislodge the blood clot forming in the socket, leading to a painful condition called dry socket. Starting on the day after your extraction, dissolve half a teaspoon of salt in a glass of warm water and gently hold the solution in your mouth over the wound. Don’t swish vigorously. Continue these gentle rinses after eating and before bed for at least five days.
How Often to Rinse Safely
For short-term use (after an extraction, during a sore throat, or to calm a canker sore), rinsing two to three times a day is typical and safe. Most people use salt water rinses for a week or two until the issue resolves.
Long-term daily use is where caution comes in. Research on mouthrinses and enamel erosion has found that prolonged exposure to certain rinse solutions causes progressive enamel loss over time. A plain salt water rinse is gentler than acidic commercial mouthwashes, but using it indefinitely as a substitute for regular mouthwash isn’t well supported. Treat it as a short-term therapeutic tool rather than a permanent part of your routine.