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Popping breath mints like it’s your job after going keto? The keto diet has been trending for a hot minute, but you probably didn’t know cutting carbs can lead to stinky breath.
Keto breath gives morning breath a run for its money, but there is something you can do about it, while still sticking to your diet plan.
Keto breath is a common side effect among people following a low carb or ketogenic diet. It’s different from your typical bad breath and has a very distinct smell and taste (you’re not gonna like that sniff test).
Keto breath symptoms include:
- metallic taste
- nail polish remover smell (mani/pedis anyone?)
- fruity or sweet smell (think rotting apples, not fresh citrus)
So why the stink? Your body’s metabolism is adjusting to having fewer carbs, which creates certain compounds that cause these dragon-worthy odors.
When following the ketogenic diet, you eat foods high in fat (yay avocados!) with moderate amounts of protein and very few carbs.
For keto followers only 5 to 10 percent of your calories in a day should come from carbs. For someone who eats 2,000 calories per day, that would be about 25 to 50 grams of carbohydrates. For reference, one slice of white bread contains almost 14 grams.
Ketosis occurs when you limit your carb intake and your body turns fat into fuel. During ketosis, byproducts called ketones increase and exit your body through your pee and your breath.
How does that make your breath smell like a nail salon? Acetone is a type of ketone body and is also an ingredient in nail polish remover (the more you know 💫).
A strange upside to having keto breath is it indicates you’re actually in ketosis, which is the whole purpose of the keto diet. Note: If you are not on the keto diet, keto breath can also be an indication of diabetes complications from diabetic ketoacidosis (DKA).
The stink’s not forever
It’s possible you may never experience keto breath, but if you do, the side effect typically doesn’t last very long. Keto breath only sticks around while your body adjusts to using fat for energy. This could be a few days or a few weeks, it varies from person to person.
While you wait for your breath to return to an acceptable smell (does anyone really have good breath?), these fresh tips may help you knock out keto breath.
1. Cut back on your protein
When protein is digested and broken down, your body creates ammonia that is released when you breathe and also when you pee. This is also a culprit of bad breath.
Try to keep protein intake to about 30 to 35 percent of your daily calories. Add a little more if you’re really hitting the gym.
2. Change your source of protein
Try eating fish one week and chicken the next week. These different protein sources contain fatty acids, but the amounts and type of fatty acid can vary. When these are digested, it can completely change the ketone bodies produced (and help your breath out!).
3. Increase your fat intake
Eating more fat can limit ketone stink creators like ammonia and acetone. A 2014 study found increasing dietary fat intake (and cutting back on protein) released less ammonia and acetone. All the more reason to get that extra guac!
4. Drink more water
Staying hydrated can help get rid of excess ketones thanks to more bathroom visits. Odor-causing ketones get released when you pee — so the more you go, the faster the ketones leave.
5. Brush your teeth… and floss
Make your hygienist happy at your next dental visit by brushing and flossing your teeth on the reg. Doing this doesn’t actually make keto breath go away, but it can get rid of any bacteria lingering in your mouth that causes additional bad breath.
6. Chew gum or have mints handy
Mask that stench with some gum or mints. Make sure to choose the sugar-free options. Regular gum and mints contain carbohydrates that can take you out of ketosis if you take too many.
7. Eat a few more carbs
This seems like the last thing you should do on the keto diet, but eating more carbs can decrease your ketone levels. Try upping your carb intake slightly (about 5 grams per day) to lower ketones and the stink that comes with them.
If you’re tracking your macronutrients very closely (fat, protein, and carbs), it’s possible you can completely prevent keto breath. There are also blood monitors, breathalyzers, and blood and urine testing strips that can measure ketone levels.
Ketone levels in the 0.5 to 3.0 millimoles per liter (mmol/L) range is a good place to be. If this number is too high, you have too many ketones that are exiting through your mouth and urine. Experiment with increasing carbohydrates slightly, and continue to monitor your ketone levels.
If you’re an avid exerciser, you may be able to utilize ketones for fuel during workouts. This is a relatively new area of research, but there is some evidence that performance can improve when the muscles learn to burn ketones for fuel during intense exercise.
After an intensive sweat session, ketones may increase periodically due to a slight decrease in your tissue’s ability to remove ketones from the blood. This will improve over time as your muscles get used to a fat fuel source instead of carbs.
If you’re following a keto diet, it’s very possible you’ll have stinky breath. Keto breath is a normal side effect and proves you’re in a state of ketosis. Thankfully the bad breath is only temporary.
As your body adjusts to more avocados and less bread, experiment with dietary changes or just let it run its course. Keto breath is a mean one, but it will go from stink to stunk.