Is It Safe For Tourists To Brush Their Teeth With Tap Water In Mexico?

You may have heard that it's best to avoid the tap water in Mexico. Though the country's water is usually purified, it picks up contaminants on its way to the sink — think bacteria, parasites, and toxic chemicals. For example, a 2018 study published in the International Journal of Environmental Research and Public Health revealed that water tested in Guadalajara had high levels of coliform bacteria and often had either too much or too little chlorine. As a result, the tap water is generally considered impotable, and gulping down a glass could leave you stuck in bed or on the toilet for days.

When it comes to brushing your teeth, however, the norms are a little less straightforward. Some users on Reddit say it's okay to brush up with the local water, while others warn that brushing your teeth can cause the same issues as drinking the water in Mexico. Unfortunately, you won't know which side is right until you try and see how your stomach responds.

To avoid leaving your vacation (or health) up to chance, it's a good idea to avoid brushing your teeth with the water from the sink. Using tap water while brushing still puts you at risk of ingesting harmful microbes and chemicals, especially if you accidentally swallow some water after rinsing your mouth. If you plan to spend your trip chowing down on tacos and exploring the amazing hidden beaches in Mexico, it's better to play it safe than miss out on the fun.

Don't do as the locals do when it comes to brushing your teeth

Often, doing as the locals do can help you learn more about a destination and experience it more authentically. However, using tap water in Mexico might be one exception. You'll likely come across some residents claiming that the water is safe for brushing your teeth and that they do it all the time without issue. And, chances are, they're not lying — small exposure to the water's microorganisms over time may not cause any digestive issues or other side effects.

However, this might not hold true for tourists who aren't accustomed to Mexico's water supply. Some locals have built up a level of immunity against certain bacteria and other contaminants found in the water, allowing them to brush their teeth or ingest small amounts of tap water without getting the dreaded traveler's belly many tourists fall victim to. If you introduce even a tiny amount of contaminated water to your system — along with all the other delicious spicy salsas, margaritas, and other new (to you) foods that might upset sensitive stomachs — your digestive system may not handle it as well as those who live in Mexico. Next time a tour guide or even a resort employee suggests it's okay to brush your teeth with the tap water, practice caution, and go with your gut (no pun intended).

The safest way to brush your teeth while in Mexico

It'll come as no surprise to learn that the safest way to brush your teeth in Mexico is to follow the same advice given when you're thirsty: Stick to bottled water. Whether you're in a big city like Mexico City or a little-known town like Careyes, purified bottled water should be easy to find, either at local shops or provided for free by your hotel. It is better to be safe than sorry.

Note that brushing with bottled water will take more time and effort, and you'll have to be mindful to not follow your usual habit of turning on the tap to wet your brush or rinse your mouth. Consider grabbing a cup or mug to avoid dirtying your bottled water. Pour a little purified water in the cup and, if you prefer, dip your toothbrush in the water before brushing. Once you're finished, take a sip of the water in the cup and swish it around to rinse your mouth. Use any leftover water to clean your toothbrush and you're done! If you get toothpaste on your face, it's generally considered safe to use water from the sink to clean it off, just as it's okay to shower using the local tap water. Be sure to keep your mouth closed when rinsing your skin to avoid accidentally swallowing the water.