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Ketosis Breath: When Your Diet Affects Your Oral Health

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Medically Reviewed By Colgate Global Scientific Communications

There are a lot of fad diets out there that claim to be the best and fastest ways you can lose weight. One diet that's created a lot of buzz is the ketogenic diet (or "keto diet" for short). Aside from helping you drop a few pounds, these diets can have some unwanted side effects to go along with lower digits on your scale. The keto diet, in particular, can cause your breath to have an unpleasant odor. There's even a name for it – ketosis breath. If you're planning to go on the keto diet, we'll let you know what it is, what side effects you can expect, and how to manage the ketosis breath you may experience.

What is the Keto Diet?

According to a review of studies on the keto diet in the journal StatPearls, before the introduction of antiepileptic agents into the medical field, the keto diet was used to help children who had epilepsy. Now, it's used to lose weight fast and has shown to be effective. However, there are short-term side effects, and long-term effects are unknown.

According to an article published by Harvard Health Publishing, the keto diet encourages low carb intake and eating large amounts of saturated fat in the form of butter, lard, and oils. So much so that fat makes up 90% of your daily calories.

Side Effects of the Keto Diet

Harvard Health Publishing recommends that your saturated fat intake not exceed 7% of your daily calories. Eating so much more than that could increase your risk of:

  • Heart disease
  • Nutrient deficiency
  • Kidney issues
  • Constipation
  • Liver problems
  • Clouded thinking
  • And, of course, ketosis breath.

If your weight is causing health problems for you and a nutritious diet and exercise has been difficult to sustain, speak with your healthcare professional about the keto diet and ask if they have any other weight-loss recommendations for your specific needs.

Ketosis and Your Breath

If you do go forward with the keto diet, you're probably wondering why it would cause you to have foul-smelling breath. The answer is in how your body breaks down fats. After swapping a typical carb-heavy diet for one that promotes fats and protein, your body goes into something called ketosis, a process where your body begins to burn fat for energy.

While in ketosis, your body converts fat cells into three types of ketones. One of these ketones, called acetone, is essentially worthless for your body to create energy. Therefore, your body releases it through your urine, sweat, and breath. Acetone is what gives your breath that distinctive "ketosis" smell, which, according to Medline Plus, can be compared to an overly sweet, fruity scent (not in a good way).

Getting Rid of Ketosis Breath

The best way to get rid of keto breath is to stop the diet. Because the scent you're giving off is coming from your lungs, practicing good oral hygiene (which is always a good idea regardless of diet) will simply be covering up the smell, not fixing it. If you've noticed that you have keto breath and you still want to continue your diet, consider some of these methods to deal with the smell:

  • Chew sugar-free gum to help stimulate saliva and freshen your breath.
  • Adjust your intake of complex carbohydrates, such as leafy green vegetables and whole grains, while continuing to avoid refined carbs.
  • Fill a water bottle and sip throughout the day.
  • Add fresh herbs to water and tea. Herbs such as clove, cinnamon, mint, and fennel are natural breath fresheners.

And, of course, continue practicing good oral hygiene. Brush at least twice a day. Clean between your teeth with interdental brushes or water flossers at least once a day. Consider using other helpful products like an antimicrobial mouthrinse and a tongue scraper.

Be sure to speak with your healthcare professional about any major changes you plan to make in your diet to achieve rapid weight loss. While it's true that a keto diet may offer benefits for your weight and overall health, it has drawbacks as well. Whatever you end up doing to drop some pounds, we hope you and your healthcare professional can find a regimen that helps you fulfill your goals and makes you smile!

Oral Care Center articles are reviewed by an oral health medical professional. This information is for educational purposes only. This content is not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of your dentist, physician or other qualified healthcare provider. 

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