Key Facts
- 80-90% of bad breath starts in the mouth.
- If you have bad breath, start by brushing your teeth and flossing regularly.
- Ask your dentist or someone close to you if they’ve noticed that you have bad breath.
About 50% of people have daytime bad breath or halitosis. The good news is there are ways to help prevent it.
What is bad breath?
Bad breath, or halitosis (the medical name) pronounced, hal-e-toe-sis, is “a noticeable and unpleasant odor in the breath.” It can be embarrassing and sometime difficult to know whether or not you have bad breath because it’s hard to smell your own breath.
What causes bad breath?
Most of the time bad breath is caused when food collects and then gets trapped between the teeth and the tongue. The food that’s stuck breaks down and releases bacteria. The bacteria then release a sulfur gas, which smells bad. Bad breath can also be caused by bacteria trapped in the sinus passages of the nose when a person has a sinus infection.
Other causes of bad breath may include:
- Smoking
- Eating certain food such as garlic, onions, coffee, etc.
- Dry mouth (when the saliva flow decreases) which can be caused by certain medicines or breathing with your mouth open
- Nasal (nose) infections or problems affecting nasal airflow or mucus production
- “Tonsilloliths”- stones that form from the tonsils and attach themselves on the tongue. The stones can cause a bad smell when a person with them coughs. Tooth decay and gum disease (sometimes called gingivitis)
- Problems with your digestive system
- Other health problems (rarely)
When do most people have bad breath?
It’s normal to have bad breath after you wake up. This is because there’s very little saliva (or spit) flowing through your mouth while you’re sleeping, which is when bacteria are most active. Your breath should improve after you brush your teeth and tongue, floss your teeth, and finish with mouth wash (if you choose).
How can I tell if I have bad breath?
It’s hard to check your own breath. Even breathing into your hand and trying to smell your breath doesn’t work. Your best bet is to ask someone you’re close to. Ask them if they’ve noticed that you have bad breath. If they say yes, ask them if it’s when you eat certain foods or whether it’s all the time. Then try the tips below and check back with the person to see if it’s made a difference.
Ways to help prevent and/or treat bad breath:
- Brush your teeth for at least 2 minutes twice a day with toothpaste that contains “fluoride”; after breakfast and before bed or (after every meal if you can).
- Floss every day. Flossing gets food particles and bacteria that your toothbrush cannot reach. If you don’t know how to floss, ask your dentist to show you.
- Brush your tongue (with a plastic tongue cleaner or tooth brush) especially the back of your tongue- where the bacteria that cause bad breath live.
- Gargle with mouthwash at bedtime. Although mouthwash is a temporary solution, it can be helpful. Ask your dentist or look for a mouthwash that has a seal from the American Dental Association.
- Don’t smoke or chew tobacco. Smoking causes bad breath and may lead to gum disease. Smoking and chewing tobacco also puts you at risk for getting oral cancer.
- Chew sugarless gum (for about 5 minutes or less) if you can’t brush right after a meal. This can help to clear away food particles left behind after eating.
- Eat foods high in fiber such as whole grains, raw fruits, and veggies.
- Staying hydrated helps to prevent dry mouth which can contribute to bad breath.
- Drink less coffee and alcohol.
These tips are your first step towards fresh breath and great dental hygiene. Eating a healthy diet and staying hydrated will help too. Avoiding food with garlic or onions and staying away from drinks such as coffee will also help.
Should I see a health care provider to treat my bad breath?
If you’ve tried many different ways to manage your bad breath without good results, it’s a good idea to make an appointment with your primary care provider or dentist.
Our health guides are developed through a systematic, rigorous process to ensure accuracy, reliability, and trustworthiness. Written and reviewed by experienced healthcare clinicians from Boston Children’s Hospital, a Harvard Medical School teaching hospital and consistently ranked as a top hospital by Newsweek and U.S. News & World Report, these guides combine clinical expertise, specialized knowledge, and evidence-based medicine. We also incorporate research and best practices from authoritative sources such as the CDC, NIH, PubMed, top medical journals, and UpToDate.com. Clinical specialists and subject matter experts review and edit each guide, reinforcing our commitment to high-quality, factual, scientifically accurate health information for young people.
