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Q: What causes morning bad breath?

A: Medically known as halitosis, it’s the almost inevitable combination of three factors: your mouth, oral bacteria and lack of saliva. The average mouth is a warm, wet and welcoming refuge for bacteria, an estimated 500 to 650 species totaling in the billions that busily feed on the amino acids, proteins and other chemicals left behind by our meals.

These processes produce odiferous compounds like hydrogen sulfide and methyl mercapatan that foul our breath. Saliva helps wash away bacteria before their work gets smelly.

When we sleep, bacteria don’t but saliva production decreases, resulting in a stronger chance of offending morning breath. It helps to brush before bed to reduce bacterial numbers and reduce their food supply, and drinking water before bed can temporarily compensate for loss of saliva, but really, the only solution is to brush and drink a glass of water first thing in the morning. Until that happens, keep your mouth closed around others.