Also known as halitosis, bad breath is caused by a variety of factors with oral bacteria being the main source. Here are five of the most common bad breath causes.

Food: While many variables determine the quality of a person's breath, the food we eat have a direct effect on breath quality. Some food inevitably lead to breath problem and the two leading food in this regard are onions and garlic. The food that we eat is broken into molecules by the digestive system and these molecules are absorbed into the body's circulatory system. These molecules are therefore deposited in the blood and as we breathe the offending odors are released.

Smoking: Smoking leads to the accumulation of tar and nicotine from the cigarette on the teeth and other soft tissues such as the tongue and gums. The tar and nicotine are foul-smelling and this directly affects the quality of a smoker's breath.

Dry mouth: A dry mouth inevitably produces bad breath. Evidence of this is available from the unpleasant smells emanating from mouths in the morning. A mouth produces foul smell in the morning because the mouth considerably dries up during sleep time due to reduced salivary flow. In addition lack of regular meals and water leads to dryness in the mouth and the attendant bad breath.

Periodontal disease: Also known as gum disease, periodontal disease develops from bacterial infection to the gums and other tissues around the teeth. This disease is common with people above the age of 35 and calls for regular examination of gums once this age is reached.

Sinus: People suffering sinuses are also likely to fall victim to bad breath. The respiratory infections caused by sinus cause the depositing of postnatal drips on the tongue. These drips are foul-smelling and are one of the leading halitosis problems.