What is Keto Breath? Why It Happens and How to Fix It

Key Takeaways

Ketones are a byproduct of entering ketosis, a metabolic state brought on by the low-carb diet known as keto
Keto breath happens when your body excretes ketones through exhalation
Keto breath may smell or taste metallic, fruity, or like nail polish remover
It develops within a few days or weeks after you start eating keto and will subside after weeks on the diet
You can make keto breath go away by adjusting your diet, drinking more water, and using breath fresheners

What is Keto Breath?

Keto breath is a distinct taste or odor in the mouth that comes from eating a ketogenic or low-carb diet. The symptoms of keto breath include:

Metallic taste
Overly sweet, like rotten fruit odor
Chemical odor, like nail polish remover

The taste or smell is a side effect that often occurs when you first start eating keto or low-carb. Not everyone who eats a low-carb diet will develop keto breath. For those who do, it’s typically temporary.

salad and avocado with flowers placed on wooden table

What Causes Keto Breath?

When your body goes into ketosis, it has two ways of excreting the high levels of ketones it produces:

Exhalation
Urination

Because of this, you may notice a change in your breath and urine. These changes signal that you’ve entered ketosis.

Keto breath usually becomes noticeable within a couple of days or weeks of starting a keto or low-carb diet. It will likely subside after a few weeks once your body gets used to the new diet.

Can You Prevent Keto Breath?

Because keto breath is a byproduct of the metabolic process, there’s no real way to prevent keto breath. The only way to completely eliminate it is to switch your eating style or wait for it to subside.

If you’re concerned about developing keto breath, you can use a ketone breath analyzer to determine how many carbs you can eat without leaving ketosis. That way, you can increase your carbs to offset bad breath while still getting the effects of ketosis.

Home Remedies For Getting Rid of Keto Breath

Although there is no way to prevent keto breath, there are a few ways to keep your breath smelling and tasting better until it goes away.

These include:

1. Drink More Water

Drinking water can help flush out the ketones more quickly through urination. It can help prevent or improve bad breath. Staying hydrated will also help alleviate dry mouth, which can be a side effect of keto.

2. Tweak Your Macros

Adjusting carbs, fat, and protein intake can help reduce keto breath. Eating high amounts of protein can worsen your breathing by producing odorous ammonia.

You can also increase your carb intake to improve your breath. Only bump up your carbs slightly if you want to stay in ketosis.

3. Use Breath Fresheners

You can mask the unpleasant odor and taste with chewing sugar-free gum, mints, and mouth spray. These won’t fix the problem, but they can improve things until keto breath goes away on its own. Always check the sugar and carbohydrate content of whatever fresheners you use to ensure they’re keto-friendly.

4. Herbal Tea

Various herbs are available which can be used as a natural breath freshener. You can add the following herbs to water and tea:⁸

Clove
Cinnamon
Mint
Fennel

5. Practice Good Oral Hygiene

Paying special attention to your oral hygiene routine can be beneficial for keto breath. Brush at least twice a day, floss once daily, and use an alcohol-free mouthwash regularly to keep your mouth clean of bacteria.

6. Give It Time

Keto breath isn’t permanent. Once your body gets used to ketosis, the odor and taste should disappear. Be patient, and your breath will return to normal within a few weeks.

What is the Keto Diet?

The ketogenic diet, also known as keto, is a popular low-carbohydrate, high-fat, and high-protein diet. Many people use it to lose or manage weight.³ People on a keto diet commonly eat foods like:

Meat and eggs
Seafood
Non-starchy vegetables and low-sugar fruits
Full-fat dairy
Nuts and seeds

Keto focuses on replacing carbs with fats in an effort to trigger a metabolic state called ketosis. During ketosis, your body produces ketones in the liver to help you burn fat for energy.

Some people adapt relatively quickly to a state of ketosis, but others do not. You must be careful when changing your body’s metabolic state. If you’re curious about trying keto, speak with your doctor to assess whether it’s the right choice.