Why You Shouldn't Rinse After Brushing

It's a small habit most people never think twice about: rinsing the mouth out with water right after brushing.

According to Dynamic Dental Care, that habit might actually be working against you. The advice from dentists is to spit the toothpaste out, not rinse it away with water. The reason comes down to toothpaste's active ingredient, fluoride, xylitol, or whatever else a given formula relies on.

Fluoride, for example, purportedly works to prevent tooth decay by remineralizing and strengthening teeth. The longer it stays on the teeth, the more time it has to work, which is why spitting out toothpaste but not rinsing is considered important for oral health.

That said, toothpaste shouldn't be swallowed in a concentrated form. According to the Oral Health Foundation and The Fluoride Action Network, swallowing toothpaste can lead to dental fluorosis, especially if done while teeth are still developing, such as in childhood.

Dental fluorosis is irreparable damage to tooth enamel that presents itself as fine white lines or flecking on the tooth's surface, and it can cause teeth to erode and crumble over time.

That possibility might sound alarming, but it's still generally best to spit rather than rinse. By spitting out toothpaste and skipping the water rinse right after, the paste mixes with saliva, which dilutes the fluoride enough to make it both effective and relatively harmless. Not rinsing lets the toothpaste stick to the teeth longer, allowing it to work into all the nooks and crannies of the mouth. Too much fluoride can damage enamel, but the consistent presence of just the right amount can help build stronger, whiter teeth over time.

The habit takes some getting used to. Keeping toothpaste in the mouth a bit longer than usual can feel strange at first, and using a tongue scraper afterward can help with that adjustment while also supporting overall oral hygiene.

If a fluoride toothpaste's balancing act feels like too much to manage, a fluoride-free toothpaste removes the concern about swallowing it or rinsing it out too early.