Is Dry Mouth a Sign of Ketosis? And Can You Fix It?
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So, your keto journey has been going great during the first few days until you noticed that your mouth feels dehydrated and you’re a little thirstier than usual.
Dry mouth is a condition that causes a parched, dry feeling in the mouth and throat. It can also cause bad breath and cracked lips.
You’re probably wondering why you’re having a dry mouth on the keto diet. Is dry mouth a sign of ketosis?
We share with you whether ketosis causes dry mouth and what you can do about it.

What is Dry Mouth?
A dry mouth, also known as xerostomia, occurs when salivary glands do not produce enough saliva. Because your mouth is dry, the breath has a foul odor, and the throat feels dry.
Dry mouth is usually a side effect of certain medications or aging issues. It can also be a result of radiation therapy for cancer.
Saliva is important for digestion because it helps moisten and break down food. It also neutralizes the acids in bacteria to limit their growth and wash away food particles.
Saliva can also enhance your ability to taste and make it easy to chew and swallow.
Dry mouth is usually caused by the following:
- side effects of medication and medical treatments
- a side effect of diseases and infections
- nerve damage
- stress
- breathing through your mouth
- dehydration
- smoking or chewing tobacco.
Frequent thirst is one symptom of a dry mouth as it results in dehydration. Other signs include:
- dryness or feeling of stickiness
- thick saliva
- bad breath
- difficulty chewing
- dry or sore throat
- dry or grooved rogue
- problems wearing dentures.
Does Ketosis Cause Dry Mouth?
Yes.
You’re probably wondering why your lips are cracked and your throat feels dry after a few weeks on the keto diet. This side effect of the diet is because of the changes in your metabolism.
Your body is shifting to the use of fat for fuel instead of carbs, so expect a lot of changes in your body. One transformation occurs in our electrolyte and fluid balance.
Nutritional ketosis increases sodium excretion by the kidneys, causing dehydration. This is why it’s recommended to up your electrolyte supplement intake.
Water itself is also released. Glycogen is stored along with water, so burning up the excessive glycogen stores comes with losing a bunch of water.
This also explains why you lose so much water weight at the beginning of your low-carb diet. Then, your body can’t carry water anymore, hence the dehydration and dry mouth.
Along with a dry mouth comes thirst, nausea, fatigue, and dark-colored urine. It also involves bad breath because a lack of saliva causes bacterial growth.
If you want to avoid dry mouth, decrease your carb intake gradually from the start of keto so you don’t lose a lot of water instantly.
But if you’re already in ketosis, try increasing your carb intake little by little, making sure you’re still in ketosis by testing your ketone levels.
Adding more carbs may reduce this dry mouth situation. Keep testing your ketone levels to know the most carbs you can eat.
Another reason ketosis causes dry mouth is because of your insulin levels. Ingesting carbs ad sugar leads to a release of insulin to combat the spike in blood sugar.
But when you limit your carb intake, your insulin levels drop and your kidneys release this stored sodium.
A dry mouth also causes bad breath because an excess of ketones are circulating in your bloodstream instead of simply being released through the urine or sweat.
As the air passes through the lungs, they are released through your breath with that fruity smell.
Who Experiences Keto Dry Mouth
Not everyone on keto gets to experience the keto dry mouth. Our bodies are all different, so we react differently to different diets.
In general, the keto dry mouth is experienced by those who are entering the state of ketosis quickly following a high-carb diet.
Rapidly increasing your fat intake and restricting carbs will take a toll on your hydration.
Some feel dryness in their throat, while others get a fruity odor in their breath. But excessive thirst always comes with a dry mouth.
Should You Worry About Keto Dry Mouth?
You don’t need to worry about your dry mouth because it is usually temporary. It is your body’s way of adjusting to a low-carb, high-fat diet.
Depending on your body, dry mouth only occurs during the first few weeks. Usually, it comes with other signs of the keto flu.
Other people don’t even experience it at all, especially if they drink more than the recommended water intake.
As your body is entering ketosis, your insulin levels lower, resulting in your body releasing more fluids.
Instead of worrying about it, take it as a good sign that you are entering ketosis!
Try testing your ketone levels to find out if you’re on the right track.
Drink More Water and Electrolyte Drinks
Dry mouth on keto is usually caused by the release of water and sodium. Compensate by increasing your water and electrolyte supplement intake.
Try drinking more than the recommended 8-10 glasses of water per day. The state of ketosis can be exhausting and dehydrating.
The goal when you have a dry mouth isn’t just to stay hydrated but to recover from dehydration.
Aside from that, you can also try electrolyte supplements like Ultima Replenisher or make your own electrolyte drink.
You need electrolytes on the keto diet to reach a healthy and comfortable level of ketosis.
With these supplements, you can replenish your body with the lost vitamins and minerals, avoiding symptoms of the keto flu.
FAQ Ketosis and the Keto Flu
Does Keto Breath Go Away?
As with dry mouth, the keto breath goes away once your body has fully adjusted to the high-fat, low-carb diet.
Keto breath is different from the usual bad breath. It has a fruity taste and smell, which is a mix of sweet and sour.
It’s normal and temporary, but there are ways to reduce bad breath when on keto.
Does Ketosis Make You Thirsty?
Yes. Ketosis can make you thirsty.
As you switch to fat for energy instead of carbs, your body adjusts by losing a significant amount of fluids.
When the last few glycogen stores are released, so is the water that comes with them.
Remember that every gram of carb is stored with about 3 grams of water.
Find out what you can do to alleviate thirst on the keto diet.
Does Ketosis Make You Sweat?
Yes.
Ketosis can make you sweat. Water released on the keto diet, which causes dehydration, is done through sweating, urinating, and breath.
However, it is also temporary and normal. Sweating is a good sign that you are entering the state of ketosis.
One way to avoid this is by taking it slow.
Check out what you can do when you’re sweating on ketosis.
What Are Other Signs of the Keto Flu?
Aside from a dry mouth, the keto diet can also cause flu-like symptoms known as the “keto flu”.
Some signs include leg cramps, constipation, heart palpitations, and reduced physical performance.
As you see, it can take a lot to reach a ketogenic state. But you don’t have to worry because not everyone experiences the keto flu.
It’s also normal and temporary. It’s a good indicator that you are getting into ketosis.
Check out what you can do about the keto flu.
What Else Can I Drink on Keto?
There are other ways to quench your thirst on keto aside from drinking water and electrolytes!
Any low-carb, sugar-free drink will do, as long as it offers some nutrients without kicking you out of ketosis.
Some options you have are flavored water, sparkling water, protein shakes, and keto energy drinks.
We have a list of drinks you can have on keto!
The Best is Yet to Come!
After the bad comes all the good. Dry mouth caused by your first time on ketosis will subside after a few weeks once your body gets used to producing ketones.
It will only take a few weeks for you to adjust. Soon, the dry mouth, dehydration, thirst, and keto breath will go away.
Remember to stay hydrated on the keto diet by drinking more water and electrolyte drinks. If you’re thinking about protein shakes for keto, we have the best keto-friendly options for you to choose from.