Dangerous breath is among the potential negative effects of a low-carb weight-reduction plan, such because the Atkins Food plan, South Seaside Food plan or Dukan Food plan. Referred to as ketosis breath, or just keto breath, the situation is usually accompanied by a foul style within the mouth. Signs like these will be distressing, however there are issues you are able to do to beat them with out undermining the objectives of your weight-reduction plan.


There are various causes of unhealthy breath. Nonetheless, with low-carb diets, there are two main culprits: ketosis (the metabolic state achieved with a low-carb weight-reduction plan) and protein metabolism.


One of many physique’s main sources of power is glucose. Glucose is created when the digestive tract breaks down carbohydrates from advanced sugars to easy glucose molecules.

If you scale back the variety of carbs you eat, your physique has to search out various gas sources (specifically fats) for power—a metabolic state generally known as ketosis.

When the physique breaks down fatty acids, it creates a byproduct generally known as ketones. Widespread ketone our bodies are available three varieties: acetoacetate, beta-hydroxybutyrate, and acetone. These ketone our bodies are usually eliminated out of your physique by means of urination and exhalation.

Should you’re on a low-carb weight-reduction plan, your physique is relying extra on fatty acids for power since you aren’t consuming as many carbohydrates. As your physique makes use of up extra fats, extra ketones will likely be launched as a byproduct of the metabolic course of at work.

The extreme accumulation of ketones in your physique can contribute to unhealthy breath. Nonetheless, the ketones you exhale have very distinctive scents—most of that are in contrast to what you’ll expertise with on a regular basis unhealthy breath (halitosis).

Protein Metabolism

Modifications in your weight-reduction plan may set off adjustments in your breath. With a low-carb weight-reduction plan, the sudden change from carbs to proteins alters how your physique metabolizes meals. The breakdown of protein within the physique creates ammonia. A sudden surge in dietary protein will solely amplify this impact, rising the quantity of ammonia in each your abdomen gases and urine.

As a result of it takes loads of water to excrete ammonia, insufficient hydration can result in a worsening of your unhealthy breath as ammonia quickly accumulates within the physique.


Keto breath varies from individual to individual however is mostly not the identical as halitosis. The unhealthy breath most of us expertise infrequently is attributable to micro organism in our mouths.

When these micro organism begin to break down the meals we eat, they create risky sulfur compounds (VSCs). Normally, these compounds have a sulfurous odor (just like rotten eggs).

With keto breath, traits of the scent fluctuate based mostly on which byproducts of protein and fats metabolism are produced. For instance:

  • Acetoacetate and beta-hydroxybutyrate may cause your breath to scent candy and fruity. Some folks describe the odor as just like bruised or rotting apples.
  • Acetone on the breath creates extra of a resiny scent (like nail polish).
  • Extra protein metabolism may cause each your breath and urine to have an aroma of ammonia.


Most often, keto breath disappears by itself—although it might take a number of weeks to a month. Should you’ve dedicated to a low-carb weight-reduction plan, listed here are just a few methods to mitigate the signs of keto breath whereas your metabolism adjusts.

  • Drink extra water. Intention for a minimum of eight 8-ounce glasses of water per day. This not solely helps flush extra ketones and VSC out of your physique, but it surely additionally aids in digestion and prevents constipation.
  • Change the stability of proteins you devour. Whereas it is a trial-and-error course of, a change of protein sources—say, from rooster to meat or meat to fish—can typically alter which ketone our bodies are being produced (primarily by the varieties of fatty acids start damaged down).
  • Improve fats consumption. Analysis means that rising fats whereas lowering protein consumption may help reduce each acetone and ammonia emissions.
  • Do not undercut the carbs. Do not be overzealous and lower out extra carbs than you want. The South Seaside Food plan, for instance, shouldn’t be as strict on the carb rely because the Atkins Food plan. Neither, nonetheless, goals for a zero-carbs coverage. Should you suspect you’ve got gone overboard on carb reducing, attempt rising your consumption of wholesome carbs throughout the prescribed restrict.
  • Apply good oral hygiene. Brush your enamel, floss, and rinse with an antibacterial mouthwash. Common tongue scraping may assist.
  • Masks your breath. Attempt pure breath fresheners (similar to mint, parsley, cloves, cinnamon, or fennel seeds) or breath capsules created from parsley oil or chlorophyll.

Sugar-free mints and gums made with xylitol may help masks unhealthy breath whereas exerting delicate antibacterial properties to regulate VSC.

A Phrase From Verywell

In case your unhealthy breath persists for greater than a few months regardless of good oral hygiene practices and your greatest efforts to staunch it, converse along with your physician or dentist. In some instances, unhealthy breath might don’t have anything to do along with your low-carb weight-reduction plan. It might be associated to dry mouth, gum illness, or medical situations similar to acid reflux disorder, diabetes, sinus issues, or liver or kidney illness.