One of the ketogenic diet’s most common side effects is keto breath. Although the bad breath is temporary, it can be unpleasant.
Keto breath is not a big deal since you can alleviate it with simple home remedies. You’ll find out exactly how that works in this article.
What Is Keto Breath?
Some people’s breath may change in the short term when they start a ketogenic diet.
However, this is not a cause for concern but a reliable sign that they are in ketosis (Musa-Veloso et al. 20021).
The broken-down fat goes to the liver, which converts some into ketones. The so-called keto breath is caused by one of these ketone bodies: acetone.
Because acetone is excreted through your breath, you can also use breath monitors to measure whether you are in ketosis.
How Does Keto Breath Smell?
Many people say the smell of acetone reminds them of nail polish remover. Others say their keto breath smells slightly fruity.
However, few people release enough acetone through their breath to make it smell like nail polish remover.
Therefore, not everybody can develop keto breath.
How Long Does Keto Breath Last?
Keto breath usually only occurs at the beginning of the ketogenic diet when the body is not yet using ketones efficiently. For this reason, more ketones are excreted through the breath.
It takes about 2-7 days to reach the metabolic state of ketosis (Cahill 20063).
Then the bad breath may occur.
The body will adapt to the new diet if you stay low-carb, high-fat.
Once your cells have learned to use ketones and the brain is sourced predominantly by them, you are fat-adapted.
Keto adaptation occurs about 3-6 weeks after switching to a ketogenic diet. Once this fat adaptation is accomplished, the bad breath disappears.
Keto breath may last for 2-5 weeks. However, straightforward home remedies exist by which you can shorten the duration.
Best Home Remedies for Keto Breath
The best ways to eliminate keto breath are simple. Here are five practical tips.
1. Drink Water
The easiest way to reduce keto breath is to drink more water. If you drink more, you will have to urinate more often. Through urine, ketones are flushed out as well.
This way, you can reduce the acetone content in the breath. Nevertheless, please do not overdo it. Excessive overhydration can be just as harmful as dehydration.
2. Use Lemons
My pro tip is to use lemon water.
Lemons and limes can help eliminate unpleasant breath because they have antibacterial properties (Tomotake et al. 20064).
Therefore, drinking lemon water is doubly effective against keto breath.
You can dilute freshly squeezed lemon or lime juice or add sliced citrus to a water carafe. Optionally, you can add fresh mint.
3. Limit Protein
If you are consuming large amounts of protein while converting to keto, it can worsen your breath.
Protein is made up of amino acids. When these are metabolized, ammonia is produced, which smells unpleasant and is measurably exhaled (Spacek et al. 20155).
Less protein in the diet can improve bad breath, help get deeper into ketosis and help become fat-adapted.
4. Stay Keto
One of the worst pieces of advice is to increase carbohydrate intake again when you experience keto breath. This way, your metabolism needs more time to adapt to a ketogenic diet. Hence, the bad breath will last longer.
If you continue to eat high-fat until you are fat-adapted, the keto breath will disappear.
Stock your pantry with grass-fed butter, extra virgin coconut, and olive oil, and get keto-adapted more quickly.
5. Be Active
Many people make the mistake of taking it easy when switching to a ketogenic diet, especially when they experience the keto flu.
When you exercise, the body is all the more compelled to use stored fat for energy.
A 30-minute walk significantly increases ketone production (Koeslag et al. 19806).
The more you move, the faster the metabolic shift takes place. Once keto-adaptation is achieved, keto breath disappears.
6. Conceal Bad Breath
There are simple home remedies that can give your breath a fresher smell:
- Fennel seeds
Due to their essential oils, these plants can positively affect your breath. That’s why it’s best to get these fresheners in pure oil. Capsules usually contain carbohydrates or other additives.
Chewing gum is not ideal since sweeteners promote cravings (Yang 20107).
7. Practice Oral Hygiene
Hygiene routines such as brushing teeth twice a day and flossing can improve ketosis oral odor. Regular tongue scraping may also help.
Those who want to put up with the sweetener can also use mouthwash.
Even though oral hygiene will not altogether remove the acetone odor, fewer bacteria in the mouth will improve the smell.
The Bad Breath Will Not Last
Keto breath can smell unpleasant but will go away. You can overcome the odor faster if you focus on healthy fats, drink enough, and exercise.
Keto breath is a definitive sign of ketosis. You are almost there, don’t stop your journey at this point.
Citrus fruits, herbs, and proper oral hygiene will help you through the temporary phase.
Eating more carbohydrates doesn’t make sense during this process because it may slow down the metabolic shift, and bad breath last longer.
Keto Breath FAQ
What does keto breath smell like?
Keto breath smells like nail polish remover.
Does keto breath go away?
Keto breath goes away once you are fat-adapted.
How do you stop bad breath on keto?
You can stop keto breath by drinking lemon water, limiting protein, increasing fat, exercising, using essential oils, and practicing oral hygiene.
Do ketones make your breath smell?
In some people, you can smell ketone bodies on their breath when they first enter ketosis.
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Mag. Stephan Lederer, MSc. is an author and blogger from Austria who writes in-depth content about health and nutrition. His book series on Interval Fasting landed #1 on the bestseller list in the German Amazon marketplace in 15 categories.
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