Bad breath, or halitosis, is a common complaint. It’s usually caused by bacteria in the mouth that produce bacteria that cause a smell. The odor occurs then the bacteria breaks down the sugars and starches we eat. But common home remedies like drinking water or green tea can alleviate the problem.

If bad breath is persistent, it can signal an underlying dental or medical problem that should be investigated by a professional. Here are some ways to treat occasional halitosis naturally:

•Water. Dry mouth can cause halitosis, so staying hydrated is important to freshen your breath. This helps the salivary glands produce enough saliva to rinse food debris from your mouth, according to Medical News Today.

•Green tea. This antioxidant-rich beverage contains epigallocatechin gallate, or EGCG, a compound that has many beneficial health benefits, including combatting oral bacteria that contributes to gum disease and halitosis. The polyphenols found in both green and black teas interact with the plaque bacteria found in your mouth, say experts at the University of Rochester Medical Center. The polyphenols kill bacteria or prevent them from manufacturing acid that attacks teeth. If your water has fluoride, a cup of tea can be a great source of this mineral, which also helps prevent cavities.

•Herbal rinses. A 2014 study found that people who used an herbal rinse containing tea tree oil, cloves, and basil had significantly reduced level of bacteria in the mouth compared to those who used commercial mouth rinses.

•Cinnamon oil. Researchers found that adding cinnamon oil to oral hygiene products may help reduce halitosis. It was found to have powerful anti-bacterial powers against certain forms of mouth bacteria. Cinnamon oil is available as an essential oil and as a food-grade oil, says Healthline. It can be found in toiletries such as toothpaste, mouthwash, soap, and body lotion. Never use essential oils directly and undiluted on the body or in the mouth. Always dilute them with carrier oils before applying as a lotion.

•Probiotic yogurt. Eating foods that coat the mouth in probiotics could help to reduce the levels of bad bacteria in the mouth which may improve bad breath. While all yogurt contains probiotics since these bacteria are necessary for turning milk into yogurt, probiotic yogurt has higher levels of these beneficial bacteria. Studies have shown that eating yogurt daily may also reduce the risk of tooth decay.

According to Medical News Today, if these self-help measure do not improve the problem, your bad breath may be due to an underlying health condition that needs medical attention. Some of these include sinus infections, chronic lung infections, digestive issues, liver disease, and diabetes.