Tag: Ketone breath

In a 2017 study published in the *Journal of Breath Research*, breath acetone was identified as a key volatile compound associated with fat loss, confirming that the distinct smell from ketones on someone's breath is a real metabolic phenomenon. This scent is a byproduct of the body burning fat for fuel instead of glucose, a state known as ketosis.

According to anecdotal evidence, a change in breath odor is one of the most common signs a person has entered ketosis. Recognizing if you can smell ketones, often referred to as 'keto breath,' can be a clear indicator of your body's metabolic state, but requires knowing what to look for.

Approximately 25% of individuals on a ketogenic diet experience 'keto mouth,' a temporary side effect characterized by bad breath and a metallic taste. This condition occurs as the body shifts its primary energy source from carbohydrates to fat, producing ketones that are released through the breath.

According to a study published by the National Institutes of Health, long-term fasting leads to a significant increase in volatile sulfur compounds (VSCs), directly contributing to unpleasant odors. If you've ever wondered, "Why does my breath smell so bad when I fast?", you're experiencing a common, temporary side effect with several clear, physiological explanations.