Almost all of us have been there - the morning after a long night you feel like a bag of bricks. Your mouth is parched, your breath reeks and your head is pounding like a thunderous bass drum. No doubt alcohol spells trouble for the body and mouth, leaving you with a case of bad breath as well as other oral health issues.
One of the biggest reasons why large quantities of alcohol are harmful is dehydration. On a basic level, alcohol is a drying agent and diuretic. Not only does it zap the mouth of saliva, the substance dehydrates cells throughout the body. It does this by blocking the release of a diuretic hormone called ADH from the pituitary gland and promoting urine production. When ADH levels plummet, the kidneys do not reabsorb as much water. As a result, your body churns out a net loss of fluid and electrolytes, thus causing dehydration.
Research has shown that for every standard drink (10 grams of alcohol) consumed, the body excretes approximately 100 milliliters of urine. Excessive alcohol consumption involving six to 10 standard drinks could lead to a net fluid loss of 600 to 1000 milliliters and cause significant dehydration.
What that means for your mouth is this: Normally, saliva acts as a cleansing agent that washes down harmful bacteria and food debris. However, without saliva, the mouth turns into a stomping ground for bad bacteria. As sulfuric anaerobic bacteria accumulate - think the rotten egg smell - you start exhaling bad breath. This is hangover halitosis.
Alcohol-induced bad breath is worsened by the same natural process that leads to morning breath. As we sleep, salivary production drops to a minimum, allowing for increased growth of bacteria that leaves behind the cringe-worthy oral odor come dawn.