Dry Fasting: Whiff Of The Dragon

Bad breath while dry fasting? It’s not the end of the world, just the end of your social life. And no, you’re not alone—although you should be, to spare others a blast of your dragon breath. 

Does dry fasting cause bad breath? During a dry fast, your body starts metabolizing fat in a process called ketosis, which often causes ‘ketosis breath.’ Reduced food and water also mean less saliva secretion, which usually diminishes bad breath. 

Dry fasting limits any water intake, causing an internal draught in your system. This water shortage leads to some whiffy downsides; however, with the right hack, you might get just be able to get by unnoticed. 

How does dry fasting cause bad breath?

The shortage of internal water—or more importantly, the shortage of saliva, which is 99% water— is the most likely reason for your bad breath during a dry fast. An average person makes 0.5 to 1.5 liters of saliva a day, a number that drops rapidly during a dry fast. Saliva is your greatest defense against bad breath.

During a dry fast, your body’s metabolism changes to create its own water. Unfortunately for your oral hygiene, most of this metabolic water is used for the body’s internal cleansing and rebuilding processes—so swishing up some mouth-watering saliva is the least of its concerns. 

Bad breath usually comes from gas-emitting bacteria below the gum and on the tongue. These bacteria eat your leftovers, break down proteins into amino acids, and release Volatile Sulphur Compounds (VSCs), which positively reek. At a regulated pH level, a consistent flow of saliva washes away most of the food particles. It inhibits bacterial growth, but in the absence of saliva, the microbes are let loose!

There are all kinds of bacteria feasting on your seconds, then dumping their stinky crap in your mouth. Some bacterial waste smells of rotten eggs (hydrogen sulfide); some like rotten cabbage (methyl mercaptan); then there’s the rotten seaweed variety: there are over 150 molecular components that make up the wretched smelling smorgasbord of sulfur compounds having a bacterial party in your mouth.

“There are more animals living in the scum on a man’s teeth than there are men in a whole kingdom.”

Anton Van Leeuwenhoek, 17th-century Dutch microscope scientist

An oral bacterial invasion, however, is not the only reason for dry fasting bad breath. 

You might be surprised to find that even after two days of dry fasting, you can still salivate at a cheesecake (albeit weakly). 

What gives?

As we discussed, your body creates its own metabolic water during a dry fast, and it does this by breaking down fat cells through a process called ketogenesis, or ketosis. 

While in ketosis, the body creates ketones as an alternate fuel source. Ketones are natural chemicals such as beta-hydroxybutyrate, acetoacetate, and acetone. These ketones are released in your urine and in your breath as the infamous ‘ketosis breath.’

Depending on your sensitivities, ketosis breath may or may not offend your senses. Many say it smells metallic, like acetone, nail polish, or fruity alcohol (think moonshine); some even say it whiffs of hamburger meat. 

Ketosis breath might not be a factor if you’ve been practicing a ketogenic diet for a while, though, as the scent subsides after your body has adjusted to a lower carb intake.

How to prevent bad breath while dry fasting 

  • Brush your teeth well 
  • Avoid mouthwash 
  • Oil pulling 
  • Gargle with baking soda
  • Flossing
  • Tongue scraping
  • Avoid smoking 
  • Visit dentist often
  • Avoid protein 
  • Avoid dairy 
  • Avoid alcohol 
  • Avoid sugary food

Brush your teeth (and take your time!)

This should be obvious, but most people brush their teeth for less than 30 seconds – you should be brushing your teeth for 2-3 minutes. Also, brushing at least twice a day is necessary for hygiene. The day before the dry fast, brush those pearly whites after every meal to make sure you’ve got as much residue out before you start the fast. 

Don’t use mouthwash

It sounds counter-intuitive, but don’t use an alcoholic mouthwash just before going into the dry fast. Generic mouthwashes usually have high quantities of alcohol, which leads to even more dry mouth. Try a mouth rinse made of water and a few drops of peppermint oil instead.

Try oil pullin

An ancient Ayurvedic practice involving swishing oil around your mouth has been known to kill bacteria and improve dental hygiene and a bunch of other diseases. It activates salivary glands and absorbs (pulls!) bacteria, viruses and protozoa out of the oral cavities. You can do this for up to 20 minutes, or 5-10 minutes at least. It’s best to use organic, cold-pressed oil such as sesame oil, sunflower oil, coconut oil, or olive oil. 

Gargle/brush with baking soda

Baking soda, or sodium bicarbonate, has been shown to effectively kill bacteria in the mouth. Studies have shown that toothpaste with high concentrations of baking soda can effectively reduce bad breath. Try a baking soda mouthwash before going into your dry fast: 2 teaspoons of baking soda to 1 cup of warm water. 


Flossing removes all the nasty debris between the teeth that the toothbrush doesn’t pick up, as the brush’s bristles can’t reach deep in between the teeth to remove it all. Flossing should be a daily or after food practice, as you don’t want anything to build up. More so before dry fasting. 

Tongue scraping 

Tongue cleaning is also an ancient practice. Research in a 2005 study found that scraping your tongue significantly reduced bacteria that cause bad breath and tooth decay. Tongue scraping can remove debris, bacteria, and dead cells that have built up on your tongue over time—all of which can add to that nasty dragon breath. 

Don’t smoke 

This should be obvious as smoking naturally gives you a smoker’s breath. But tobacco also causes dry mouth and cavity-fighting antibodies in your saliva. 

Visit dentist often 

Do yourself a favor and get dental care often to ensure there are no nasties in your mouth that can fester during your dry fast. If you suspect you have a dental condition, maybe go once every 4 months to make sure it’s in check instead of the recommended once every 6 months, just to make sure it’s not a pre-existing dental situation that’s making your breath worse. 

Self-mouthwash tip 

Think of lemon for 10 seconds—your mouth will start watering. Milk (lemon!) this thought for 30 seconds to make extra saliva and then swish it around your mouth, giving it a self-induced mouthwash. Bravo. You’ve just eaten an imaginary lemon and got a citrusy fresh mouth. You’re welcome. 

Foods to avoid to prevent dry fasting bad breath

Eat less protein 

Proteins have an ammonia smell when they break down, so eating less protein helps reduce this smell. The ammonia is released through urination and exhalation, so do yourself a favor and go easy on the meat! 

Avoid milk and dairy 

Dairy products like milk and cheese contain amino acids that react with mouth bacteria to produce that rotten egg smell (remember hydrogen sulfide?). These also leave a white coating on the tongue that you might notice sometimes. So eating less dairy before entering a dry fast will definitely help!

Avoid alcohol 

Naturally, don’t consume alcohol because you will become dehydrated, which is really not the way you want to enter a dry fast anyway.

Avoid sugary food

Sugary foods can increase the number of bacteria in the mouth, which leads to a worse smell. Avoid pastries or sweets and anything that even whiffs of Nutella!

Hopefully, you’re now feeling minty fresh and ready to take on a dry fast with confidence! But if you want to learn more about dry fasting for rapid weight loss and age reversal, check out my new video course, 25 Again! The Dry Fasting Lifestyle For A Younger, Slimmer You. See you there!

***Disclaimer: I am not a doctor/ physician, and although I have a bachelor’s degree in Biomedical Science, I cannot and do not hold myself to be a medical professional (“Medical Provider”). This article does not contain medical /health advice. The medical/ health information here is for general and educational purposes only. It is my opinion, based on my research and personal experience, and not a substitute for professional advice by your health care provider. Please consult with a professional before acting on the information here, and do not disregard medical advice or delay seeking medical attention because of anything you read in this article. THE USE OR RELIANCE OF ANY OF THE INFORMATION ON THIS WEBSITE IS SOLELY AT YOUR OWN RISK.***



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