As you already know, the keto diet is great for weight loss, getting rid of brain fog, decreasing your risk for heart disease, and setting yourself up for long-term health.
But how do you know if your keto diet is actually working?
It’s pretty simple: there are specific ketosis symptoms and signs of ketosis you’ll experience so you don’t have to stress if you’re doing the keto diet “right” or not.
And that’s what this article will cover – the 11 main signs of ketosis.
To get you started, here’s a quick video covering the first 6 ketosis symptoms:
11 Signs of Ketosis
Here are 11 signs of ketosis. You can use these keto symptoms as a gauge to see if you’re in ketosis. Some of these can be thought of as ketosis side effects. Thankfully, the less pleasant ones are temporary.
1. Increased Thirst and A Dry Mouth
Many keto dieters report having a dry mouth and feeling a lot thirstier than usual. If that’s something you’re experiencing, don’t worry. It’s one of the most common signs of ketosis. That means your diet is working!
When you first go Keto, you’ll be excreting a lot of water – that’s one of the ketosis side effects, and it’s related to switching to a diet high in fat and protein, but low in carbs. And you’ll be losing a lot of electrolytes (like sodium, potassium, and magnesium) along with the water.
You’ll not only be losing more sodium than before, you’ll also be eating less sodium than before. And that’s because you’re giving up processed foods. Think about how salty a bag of chips is – most highly processed foods have a lot of sodium in them. And when you cut those foods out of your diet, you’re also cutting out your main source of sodium.
This combination causes a drop in your electrolyte levels and the amount of fluid in your body. So you start feeling thirsty!
If you’re feeling thirsty and your mouth is dry, that’s a good sign you’re in ketosis!
But it’s also important to do something about this symptom: so drink more water, consider adding salt to your meals and make sure you’re eating foods rich in electrolytes.
2. Lack of Appetite
Feeling less hungry is another commonly reported side effect of a successful ketogenic diet.
That’s because a ketogenic diet affects your hunger hormones in a way that significantly reduces your appetite (there’s a study with proof here).
As a result, one of the best Keto diet side effects is reduced hunger levels (have a look at this study).
“Many dieters complain that hunger sabotages their success,” explains Dr. Vincent M. Pedre, M.D. “Ghrelin is your hunger hormone that tells you to eat. Research shows ketogenic diets suppress ghrelin, keeping you fuller longer. That makes sense: When you’re eating sufficient dietary fat and calories, you’re unlikely to be hungry.”
Plus, most of us typically have weeks or even months worth of energy stored in our bodies as fats. Which means when you’re in ketosis and have a calorie deficit, your body starts using up this stored energy source, greatly reducing your feelings of hunger.
If you find you aren’t hungry or are eating less often, you may be in ketosis.
3. Rapid Weight Loss
Rapid weight loss in the first week can be a good sign that you’ve reached ketosis.
When you’re in a ketogenic state, your body sheds stored carbs and excess water. And that means you’ll initially see a rapid drop in your weight.
Once the bloating and water weight is gone, you’ll still lose weight – but less dramatically. Your body will start to burn up excess body fat, and you’ll find yourself slimming down in a safe manner.
Rapid weight loss is a common keto diet side effect, as you drastically reduce your carb intake which gets rid of water weight.
4. Smelly Breath or “Keto Breath”
One of the less desirable ketosis side effects after first switching to Keto is having unpleasant-smelling breath.
This happens because your body is making ketones which it can’t use yet – it hasn’t become keto-adapted. And it expels some of these excess ketones via your breath, in particular, a type of ketone called acetone.
Don’t worry, keto breath goes away pretty quickly and if it bothers you or your loved ones, then try adding some mint leaves to your water or even a few drops of mint essential oil to your water. Brushing your teeth more often is another option.
Having bad breath is one of the most reliable signs of ketosis.
Although it will disappear naturally, you can take steps to minimize it in the meantime: many keto dieters brush their teeth several times a day, in the beginning, to keep their breath smelling fresh.
5. More Ketones in Your Blood
Measuring the level of ketones in your blood is a sure-fire way to tell if you’re in ketosis.
When you’re in ketosis, your body starts burning more fat for energy and relies less on carbohydrates/sugars. Ketones are made as a byproduct of the breakdown of fat, and that’s why the number of ketones in your blood will increase when you’re in ketosis.
You can measure your ketone levels by using a specialized blood-ketone meter. It measures the levels of beta-hydroxybutyrate (BHB) in your bloodstream – which is the primary ketone your body produces when you’re in ketosis.
The most accurate way to tell if you are in ketosis is using a blood ketone meter to test your ketone levels.
And if you want more information on what your ketone levels mean plus what levels you should be aiming for, have a look at our article on What Are The Optimal Ketone Levels For A Ketogenic Diet?
6. More Ketones in Your Breath or Urine
Measuring the levels of ketones in your urine can give you a ballpark estimate of whether you’re in ketosis or not. And the same goes for the ketone levels of your breath.
This study concluded that “breath acetone is as good a predictor of ketosis as is urinary acetoacetate.” These types of ketones are expelled as waste through your urine as well as your breath. Which means it’s possible to measure your ketone levels via breath testers and urine strips.
In fact, Dr. Michael R. Eades, M.D. notes, “If you are righteously following a low-carb diet – especially in the early days – you may produce enough ketones to register on a breathalyzer should you get stopped on suspicion of being drunk.”
The main benefit of breath ketone testing is that it’s noninvasive. For the urine test, you pee on a stick that changes colors depending on the levels of ketones detected. And for the breath test, you breathe into a meter that then gives you a reading of how much ketones are detected on your breath.
However, both of these method of testing can be less accurate and most people wanting to test ketones stick to the blood meter still.
You can measure your ketone levels by using urine strips or a breath analyzer to check if you’re in ketosis. However, both these tests are less accurate than the blood meters.
7. Increased Focus and Energy Over the Long-Term
Some Keto diet side effects are found most in people who stick to a ketogenic diet long-term. For example, long-term Keto dieters often report reduced brain fog, increased mental clarity and an improved ability to remain focused.
That’s because following a ketogenic diet stabilizes your blood sugar levels.
Registered Nurse Jami Cooley, RN says, “Ketones are able to generate greater amounts of energy per molecule than glucose. Therefore, the ketones create a much more sustainable energy source for the body and do not cause the blood sugar spikes that glucose causes.”
You’re no longer eating many carbs, so you don’t experience blood sugar spikes followed by crashes. And that’s great news for your brain!
But it takes time for your body to adapt to burning fat rather than carbs for fuel. So if you’ve just started your keto diet, you’ll have to be a little patient before you experience this particular ketosis symptom for yourself.
If you find you feel more clear-headed and your energy levels are more stable, it’s a good sign you are in ketosis.
8. Increased Fatigue or “Keto Flu” in the Short-Term
If you feel weak and fatigued when you first make the switch to keto, that can be a sign that your keto diet is working.
When your body first has to make the switch to burning fats instead of carbs, it can take anywhere from 7 to 30 days before it becomes fully adapted. And while it adjusts, you’ll experience one of the most well known keto diet side effects out there: the keto flu.
“Symptoms of the keto flu include cravings, fatigue, insomnia, irritability, muscle cramps, or nausea,” says Certified Health Coach Dr. Christina Tarantola, PharmD, CHC. “Depending on the symptoms, adding Himalayan sea salt to beverages or food, increasing fat, magnesium, and potassium, and staying hydrated, can all help. This tends to last about 1 week and varies with each person.”
The exact symptoms differ from person to person. Some people get slight headaches. Others find it hard to focus. Others feel tired. This is often called Keto Flu because it can feel like flu-like symptoms, and even though Keto flu feels uncomfortable, just remember that it’s only temporary.
Often many people give up before their body fully adjusts to burning fat, so it’s important you stay motivated and use our 6 Strategies for Curing Keto Flu to get through this initial stage so you can experience the full benefits of Keto.
Feelings of fatigue and low energy, are common during the initial stages of a keto diet. It’s a sign that things are on the right track and you’re entering ketosis.
And you’ll soon start to experience the opposite effect once your body becomes adapted to burning fat and running off ketones!
9. Drop in Performance over the Short-Term
This goes hand-in-hand with the keto flu, so a drop in performance can be a sign that things are moving in the right direction.
Naturally, a lack of energy or weakness will also lead to decreased physical performance during exercise. You’ll experience a drop in your athletic performance while your body adapts to its new fuel source.
However, after a few weeks, your performance during your workouts should return to normal as your body will start burning fat more efficiently.
Experiencing a short-term decrease in your athletic performance is a sign your body is adapting to ketosis. And you should be back to your normal performance levels after a few weeks!
10. Digestive Issues
A ketogenic diet can give you digestive issues while your body adapts to your new diet.
Constipation and diarrhea are common side-effects which early-stage keto dieters experience. And they’re a sign your body is adjusting to a higher fat intake.
Luckily, like many of the other negatives you may experience when first going keto, they’re only temporary. They’ll pass as your body adjusts to a higher fat intake and getting energy from different foods than before.
Registered Dietitian Lauren Popeck, RD, says, “Constipation and diarrhea can result in the beginning as the body adjusts to processing different proportions of food. Eating low-carb vegetables can help.”
If you want to decrease the digestive discomfort, then make the switch to a Keto diet slowly so that your body has time to adjust. Eating vegetables is still important as it helps you get sufficient fiber to help your digestive system stay healthy.
Check out this list of low carb veggies to see which you ones you should adding to your keto diet. And if you need a keto fiber supplement, then CoBionic Foundation is a comprehensive prebiotic fiber that can really help.
Digestive issues are common when your first make the switch to a ketogenic diet, and they should pass with time. They’re just another sign your body is adapting.
However, if you don’t see signs of improvement, it may be a good idea to check if intolerances to specific foods could be causing the problem. And increasing your fat intake gradually can help prevent digestive issues in the first place.
Insomnia is one of the most common ketosis symptoms.
Many keto dieters reporting waking up during the night and experiencing restlessness during sleep. This happens because you’re dropping most of the carbs from your diets, and carbs are known for making you feel sleepy (just think about how much you need a nap after a large plate of pasta).
Insomnia normally goes away after a few weeks. And many folks find that they sleep better than ever before after they’ve been on the diet for a month or so and their body has become keto-adapted.
Another common report for Keto dieters is that they often need less sleep than before! But this is a long-term benefit that you’ll need to wait a few weeks to experience.
Trouble sleeping is common in the early stages of a ketogenic diet. However, sleep usually improves after a few weeks.
Pinterest Image For 11 Ketosis Symptoms and Signs
Please pin the image below so that you and others can quickly and easily refer to the list and check if you’re in ketosis or not.
The Best Way To Tell If You’re in Ketosis
As you can tell from the list above, there are various signs of ketosis that indicate your body is producing ketones.
But at the end of the day, if you really want to make sure you’re in ketosis, then testing your ketone levels is the more accurate method.
Here’s a quick recap of the three main ways you can test for ketosis:
- Urine test strips
- Breath analyzers
- Blood-ketone meters
The most accurate method is to use the blood-ketone meter. These meters will show you the current level of BHB ketones in your blood, with a high degree of accuracy. The method of testing is similar to blood glucose meters – you prick your finger and draw a drop of blood that you run through a test strip attached to a meter.
The disadvantage is that these meters and their test strips are a lot more expensive than the urine strips or breath analyzers. However, if accuracy is important to you, then a blood-ketone meter is the best choice.
If you want more info about testing for ketone levels or what your optimal ketone levels are, then check out this post here.
And for more specific information about testing ketones in urine (whether it’s worth it and how to do it), check out our post here.
Worried You’re Not in Ketosis?
If you’re not experiencing any of the ketosis side effects I listed above, you might be worried you’re not in ketosis.
Don’t be: it’s not the end of the world if you aren’t always in ketosis.
Because the truth is, it’s more important to focus on feeling great and losing excess weight. You don’t get too caught up in worrying if you have 3 mmol/L or 2.5 mmol/L of ketones in your blood. If you’re getting results and losing weight, then chalk it up to a win!
And if you need any clarification or help, don’t hesitate to post in our forum. We’re here to help.
Don’t stress too much about your ketone levels
The key takeaway I want to you to remember is this: while it’s good to know whether you’re in ketosis or not, you don’t need to get too fixated on your ketone levels it and stress yourself out about it.
Instead, focus on how you’re feeling and the results you’re seeing:
- Did you start keto to help you lose weight? Then focus on that as your end goal – you can often accomplish it without getting high ketone levels.
- Have your energy levels increased since starting keto? Are you feeling more focused and positive? Then your keto diet is going brilliantly, no matter what your ketone levels are.
As long as you’re reducing your carb intake, steering clear of processed junk foods, and filling your diet with a wide variety of nutrient-dense foods, you’ll be doing your body good.
And that will be reflected in the way you look and feel, whether you’re in ketosis or not!