Dr. Harold Katz, creator of the TheraBreath system, states that garlic consumption and consumption of herbal supplements containing garlic are two fairly common causes of garlic breath. Additional causes include selenium toxicity and tellurium poisoning.
Dr. Harold Katz explains that garlic oils and extracts that are found in certain supplements can cause the breath to smell like garlic. Dr. Katz points out that selenium toxicity is rare and typically occurs in individuals who are exposed to selenium in the workplace. A common sign of tellurium poisoning is garlic-tinged breath. Dr. Katz indicates that both elements are found in the same periodic table group as sulfur, an element found in garlic that contributes to the actual scent of garlic breath.
According to Dr. Katz, the easiest way to treat garlic breath caused by garlic ingestion or the ingestion of supplements containing garlic is with the use of an alcohol-free mouthwash and breath-freshening toothpaste. Dr. Katz also recommends that anyone experiencing garlic breath following selenium or tellurium exposure should seek immediate medical assistance.
According to the Mayo Clinic, garlic causes odorous breath in two ways. When garlic breaks down around the teeth, it can increase the production of bacteria in the mouth, leading to a foul odor. Additionally, digested garlic enters the bloodstream, where it travels to the lungs and results in odorous breath.