There are many causes of bad breath, but the most frequent cause is a reasonably easy fix. Most cases of bad breath come from improper oral hygiene. The plaque on your teeth can cause bad breath because the bacteria contained in plaque produce odor. It can occur from not brushing long enough (for 2 minutes 2 times a day) or not brushing properly (missing teeth or not brushing to the gumline). Bad breath as a result of improper oral hygiene can also occur if a person is not flossing daily or nor flossing correctly. This is because plaque and bacteria between your teeth are not removed by brushing, and like the plaque you brush off your teeth, it comes back daily.
If you know your oral hygiene is not the issue, there are other causes of bad breath to consider. Certain foods, such as onions and garlic, can cause bad breath. This is because after the food is digested, it enters your bloodstream and is carried to your lungs, affecting your breath. Another cause of bad breath is dry mouth. Saliva helps control bad breath by removing particles that cause bad odors. Dry mouth can be naturally occurring or caused by certain medications. Your mouth is naturally dry when you sleep, leading to morning breath.
Bad breath can occur due to infection or inflammation in the nose, sinuses, or throat which can cause postnasal drip. Chronic reflux of stomach acids can also contribute to bad breath. If you have bad breath and have made efforts to improve your oral hygiene (brushing to your gums twice a day, flossing, brushing your tongue) you may want to visit your physician to find out the cause.