ketosis symptoms featured image

How Many of These 10 Ketosis Symptoms & Signs Do You Know?

Have you started following the Keto diet plan for weight loss? The eating trend has taken the western world by storm and could help you to maintain a healthy weight. If you want to start burning any excess fat, you need to make sure that your body switches into the ketosis state. As soon as this stage of physiology begins, you will notice certain ketosis symptoms. Understanding these signs is a sure-fire way to keep yourself on track. So, how many of these do you know?

Symptom #1: Increased Ketone Levels

Needless to say, one of the most common ketosis symptoms is an increased level of ketones in your blood, urine, and breath.[1][2] When you’re following the Keto diet, continually checking these levels could be a smart way to figure out whether you have entered ketosis. Of course, you will need special equipment to check your levels on a regular basis. Luckily, you can get both blood and urine ketosis strips online.

Symptom #2: Bad Breath

As your ketone levels rise, your body goes through certain changes. For instance, one form of ketone, known as acetone, can leave your body via either your breath or urine.[3] Since the molecule has a rather strong smell, you may find that your breath starts to smell quite fruity or even sweet. While this is one of the most irritating symptoms of ketosis, you do have options here. You can deal with the problem by regularly brushing your teeth or using breath mints to mask the scent.

Woman on scale happy with ketosis weight loss
While entering ketosis is a sign of Keto diet success, it does come with some uncomfortable symptoms.

Symptom #3: Boosted Weight Loss

Starting the Keto diet to slim down? You’ll be pleased to know that one of the main ketosis symptoms is ongoing weight loss. Research published in the US National Library of Medicine has linked this type of eating plan with sustainable weight loss and weight management.[4] It goes without saying that you should also make sure that you are leading a healthy and active lifestyle when following the diet. Regularly weighing yourself will help you to keep an eye on how much you’re shedding on a weekly basis.

Symptom #4: Loss of Appetite

Perhaps one of the more surprising signs of ketosis is a loss of hunger. Research from the US National Library of Medicine suggests that following the Ketogenic diet could help to suppress a person’s appetite.[5] If you tend to struggle when it comes to portion sizes and snacking, you may find that this helps you with your weight loss journey.

Tired woman in ketosis asleep at her computer

Symptom #5: Short-Term Fatigue 

Changing your diet can be something of a struggle. One of the symptoms of ketosis that you may discover here is fatigue due to the sudden change in your food intake. It’s important to remember that this period will not last forever. It is temporary. For that reason, you will need to work through it and simply wait until you start to feel less tired. Many people quit the Keto diet before it takes full effect but you should try to keep going.

Symptom #6: Increased Energy

While one of the initial symptoms you’ll experience may be fatigue, this will soon pass. The sign is often followed by an energetic phase. Research published in the US National Library of Medicine suggests that ketosis is linked to enhanced energy.[6] Should you find that you feel more awake during the day, that may be a sign that your body is entering the ketosis state.

Woman in ketosis super focused at work
One of the most surprising signs you may experience when you’re in ketosis is an increase in focus.

Symptom #7: More Focus

If you’re hoping to excel at studying or in your role, this change in dietary habits could be a good one. One study published in the US National Library of Medicine found that people on a low-carb diet reported more focus and less confusion.[7] With that in mind, you may find that you have higher levels of focus and attention when you start to follow the Keto diet. You may want to make a note of how you feel by journaling each day.

Symptom #8: Short-Term Exercise Issues

Are you a total gym bunny? If you love nothing more than hitting the gym on a daily basis, you may find that the Keto diet presents an issue to you. Since you’re cutting the carbs out of your diet, you could find that you struggle with energy levels. In the short term, that could mean that exercising and leading an active lifestyle is more difficult. During this period, you should consider slowing down on your regular routine for a while. When the fatigue passes, you will be able to pick up where you left off.

woman in ketosis with headaches

Symptom #9: Headaches

Next up, let’s take a look at one of the worst ketosis symptoms you need to know about. Research published in the US National Library of Medicine suggests that the ketosis stage could be linked with headaches.[8] You may find that you get regular headaches when you first begin to follow the eating plan. Ensure that you hydrate well enough and monitor the situation. If this sign is an ongoing issue, you may want to see a doctor.

Symptom #10: Keto Flu

When it comes to ketosis symptoms, here’s one that you may have heard about. Keto flu is the name given to a variety of symptoms including feelings of weakness, constipation, and diarrhea.[9] These signs of ketosis usually tend to occur between days one and four of following the diet and could be due to water loss and lowered insulin levels.[10] If you are suffering from these symptoms, remember that they should be brief. Keep an eye on the situation and, if they last for more than a few days, seek medical help.

What Should I Do Once I Notice Signs of Ketosis?

The main aim of looking out for these ketosis symptoms is to get an idea of how long it takes to get into ketosis. Once you find that you have some of these symptoms, it may mean that you are in a Ketogenic state which could mean that you burn more fat. Of course, if any of the ketosis symptoms are causing you ongoing health issues, you may need to speak to a doctor or nutritionist about reassessing your current diet plan.

How Many Symptoms of Ketosis Should I Look Out For?

keto foods with a keto food chart
While the symptoms we’ve described above are experienced by many people, there are no hard and fast rules. Everyone’s body is different, after all!

When your body has officially entered the ketosis stage, you may notice any number of these symptoms. There are no hard and fast rules here. The most important sign you need to look out for is weight loss. Since this is usually the primary goal of following the Keto diet, it’s certainly something you should be monitoring as much as possible.

If you’re unsure as to whether you’re in ketosis, you may also find that using strip tests is useful. Taking note of your ketone levels will allow you to figure out whether you’re on the right track or, conversely, whether you should adapt your diet accordingly.

Do You Know These 10 Ketosis Symptoms & Signs?


Have you noticed these ten ketosis signs? Paying close attention to your body is always a smart move whenever you start a new diet. If you notice these telltale signs, you may find that you start to lose weight in a reliable and manageable way.


Scientific References: