A Complete Guide On How To Treat Keto Flu Symptoms 

Keto Flu Symptoms

Keto Flu Symptoms

Updated on 9/30/2023
Natalia MarinBy Natalia Marin
Natalia Marin
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In recent years, the ketogenic diet has seen a significant increase in popularity due to its reputation as an all-natural approach to accomplishing one's weight loss and health improvement goals. Keto flu symptoms reputation stems from the fact that the ketogenic diet is low in carbohydrates and high in fat.

The carbohydrate component of the diet is deficient, yet it contains a sizeable amount of fat and only a tiny amount of protein overall. The diet includes a minimal amount of carbs.

Even though the diet is thought to be risk-free for the vast majority of people, it has been linked to various unfavorable outcomes that are unacceptable. These effects include:

Dieters who follow the ketogenic diet have given origin to the term "the keto flu," which is also sometimes known as "the carb flu," to explain the symptoms they encounter after commencing the diet for the first time. The ketogenic diet is also commonly known as "the low-carb diet."

This article defines the keto flu, explores why people get it and explains how you can address its symptoms to help people feel better.

What Is The Keto Flu?

what is keto flu

what is keto flu

The term "keto flu" refers to symptoms experienced by some people when they first begin the ketogenic diet. These symptoms can range from mild to severe, and the severity of these symptoms can vary significantly from person to person.

Because the body is adapting to a new diet consisting of very few carbohydrates, these symptoms are expected during this transition time. These symptoms are a direct result of the adjustment that has taken place, and they might feel quite similar to having the flu.

If you cut down on the number of carbohydrates you eat, you will force your body to produce ketones rather than glucose as an energy source. Ketones have a higher energy density than glucose and the breakdown of fat results in the production of ketone bodies.

Ketones are a metabolic byproduct formed when one consumes a diet that is recognized as ketogenic. Ketones are derived from the breakdown of fat rather than carbohydrates. During a ketogenic diet, this occurs as a natural byproduct of fat study. As soon as ketones are created, they immediately take over as the body's primary fuel source.

Fat is never utilized as a primary fuel source; instead, it is stored for usage if glucose cannot be used as a fuel source.

This metabolic state is called ketosis when glucose is used to make energy from fat rather than the other way around. Ketosis is the name given to the condition that occurs. When certain conditions are satisfied, such as being exceedingly hungry or fasting for a considerable amount of time, this can make happen. Other prerequisites include being unable to consume any food.

Keto Flu Symptoms

Keto Flu Symptoms

On the other hand, ketosis is a condition that can also be reached by adhering to a diet in which the consumption of carbohydrates is kept to an absolute minimum. That can bring about the situation.

When following a ketogenic diet, an individual's daily consumption of carbs is often lowered to less than 50 grams.

This sudden reduction may act as a shock to the body and may create symptoms that are similar to those noticed during withdrawal from the substance. These symptoms may include: These symptoms are comparable to those that are felt during the process of withdrawing from a habit-forming stimulant such as caffeine.


People who have recently begun following a ketogenic diet that is very low in carbs may experience symptoms similar to the flu. These symptoms may include fever, chills, body aches, and headaches. "Keto flu" is a phrase coined to describe these symptoms, which were the original inspiration for the term.


It will probably take time for your body to become acclimated to the new eating pattern you are asking it to follow because switching to a very low-carb diet is such a significant adjustment. That is because converting to a very low-carb diet is a significant shift.

Certain people may have a challenging time adjusting during this period.

Keto Flu Symptoms

Keto Flu Symptoms

It is conceivable that you will begin to experience symptoms of what is known as "the keto flu" during the first few days of starting a ketogenic diet. That will occur after you have decreased the number of carbohydrates consumed.

The symptoms likely felt by one individual with the same condition as another person with the exact condition will not be comparable to those touched by the second person.

The transition to a ketogenic diet may not produce any unpleasant side effects for some people. Nonetheless, some people might experience some or all of the following symptoms at some point throughout the process:

  • Nausea
  • Vomiting
  • Constipation
  • Diarrhea
  • Headache
  • Irritability
  • Weakness
  • Muscle cramps
  • Dizziness
  • Unable to concentrate due to distractions
  • A queasy feeling that one has in their stomach
  • Muscle soreness
  • Having problems getting to sleep or remaining asleep all through the night
  • a craving for a wide variety of cakes, cookies, and pastries

People who have only recently begun following a ketogenic diet frequently report experiencing these symptoms, which can be pretty upsetting. These symptoms can be caused by a shift in the metabolic state from glycogen to ketones.

Keto Flu Symptoms

Keto Flu Symptoms

Although the symptoms usually go away after about a week, there is a chance that some people will continue to experience them for a significantly longer amount of time. That is because some people have immune systems that are far weaker than others.

Although there are solutions available, the fact that there are ways to lessen the severity of these unpleasant effects may lead some dieters to give up on their attempts altogether, despite the fact that there are options available.


When starting a ketogenic diet, some people may experience diarrhea, weariness, muscle stiffness, and cravings for items high in sugar. It's possible that some people won't share any of these adverse effects at all.

How To Get Rid Of The Keto Flu

The keto flu is a sickness that can cause a person to feel extremely ill and potentially render them incapable of normal daily activities.

Fortunately, treatments can lessen the severity of these symptoms, similar to those of the flu, and help your body have an easier time navigating the transition phase. These symptoms are akin to those of the flu and are comparable to those experienced by people with the flu.

Stay Hydrated

Stay Hydrated

Stay Hydrated

Consuming the amount of water that is advised to be consumed on a daily basis can not only help to develop and maintain a healthy state of being, but it also has the potential to treat or alleviate specific conditions.

A quick drop in the quantity of water stored in the body is one of the potentially detrimental effects of following a ketogenic diet. That raises the likelihood of being dehydrated, which is another one of the potential unfavorable effects.

That is because glycogen, the form of carbohydrates stored in the body, binds to water. The presence of glycogen in the body is responsible for this phenomenon, which can be explained as follows: When there is a reduction in the number of carbohydrates taken in through diet. There is a corresponding steep decline in the quantities of glycogen found in the body, as well as an increase in the amount of excreted water. That is because glycogen is a stored form of sugar that can be broken down into glucose when the body needs it.

By keeping a healthy level of water in the body at all times, it may be feasible to reduce symptoms such as weariness and cramping in the muscles.

It is of the utmost significance to ensure that any fluids lost during an episode of diarrhea caused by the keto flu, which can lead to an even higher loss of fluids, are replenished as quickly as possible. An individual can lose even more fluids due to the keto flu.

Avoid Intense Exercise

Avoid Intense Exercise

Avoid Intense Exercise

Those who are feeling the effects of the keto flu should avoid engaging in excessive physical activity as much as possible until their symptoms have subsided. It is essential to exercise to maintain a healthy body weight and overall good health; however, it is advised to avoid intense exercise while experiencing keto flu symptoms because it can worsen symptoms. Although exercising is essential, avoiding intense exercise while experiencing keto flu symptoms is advised because it can worsen symptoms.

In the first week of following a ketogenic diet, it is not abnormal to experience symptoms such as fatigue, muscle cramps, and stomach ache. These side effects are common. As a result, it is likely to be in your best interest to give your body some rest during this time.

When your body adjusts to the new fuel sources, you may need to reduce the number of strenuous activities you participate in, such as intense riding, running, lifting weights, and strenuous workouts. If this is the case, you should try to limit your participation in these activities as much as possible. If this is the case, you need to prioritize reducing the total amount of time you spend participating in activities like these.

Participating in low-intensity aerobic exercises like walking, yoga, or riding at a leisurely pace are some examples of the types of physical activity that have the potential to help ease the symptoms of the keto flu. On the other hand, if you think you could be suffering from the keto flu, you should avoid engaging in activities that require a higher level of intensity.

Replace Electrolytes

Replace Electrolytes

Replace Electrolytes

There is a possibility that introducing electrolytes back into your diet will assist in alleviating some of the symptoms of the keto flu.

The process by which the body removes glucose from the bloodstream is facilitated by the hormone insulin, a crucial endocrine component. Insulin is an important hormone that plays a function in the process, and when a person consumes a ketogenic diet, their insulin levels go down. That is a good thing, as insulin is a crucial hormone that plays a role in the process.

The kidneys initiate the process of draining excess salt out of the body when insulin levels drop, which is a process that is created when insulin levels decline.

On the ketogenic diet, it is strongly discouraged to consume a wide variety of foods that are high in potassium. This restriction applies to both vegetables and fruits. These foods have a high starch content and include fruits, vegetables, and beans on their list of components. In addition, the starch level is relatively high.

During the period of adaptation to the diet, one of the most effective ways to maintain one's strength and stamina is to ensure that one receives appropriate quantities of the necessary nutrients. You can accomplish this by providing one consumes adequate amounts of essential nutrients. You can achieve this by ensuring one consumes the appropriate quantity of each vitamin in their diet.

You may keep a healthy balance of electrolytes by salting meals to taste and eating foods that are high in potassium and favorable to the ketogenic diet. These foods will help you maintain a healthy balance of electrolytes. You will have an easier time keeping a suitable fluid and electrolyte balance if you do both of these things. Avocados and dark green leafy vegetables are two examples of foods high in the mineral potassium, and bananas are yet another good illustration.

It has been shown that the mineral magnesium, which can be found in abundant supply in the foods above, helps alleviate various symptoms, including aches and pains and issues with sleep and headaches.

Get Proper Sleep

Get Proper Sleep

Get Proper Sleep

In some instances, attempting to adapt to a ketogenic diet is accompanied by side effects such as feelings of exhaustion and frustration.

If you don't get enough sleep, your body will produce more stress hormone cortisol, which can hurt your mood and make the keto flu symptoms even more severe. If you don't get enough sleep, your body will manufacture more of the stress hormone cortisol. If you don't get enough sleep, your body will create more of the hormone cortisol, which is associated with stress.

If you find that you have trouble falling asleep or staying asleep, put one of the following suggestions into practice and see if it helps:

  • Because caffeine is a stimulant and has been demonstrated to have an effect that is detrimental to sleep, it is recommended that you cut down on the amount of caffeine you drink. If you consume beverages that include caffeine, you should limit your consumption to the earlier hours of the day so that it does not interfere with your ability to go to sleep or remain asleep. Caffeine can keep you awake for several hours after you drink it.
  • When electronic devices in the bedroom, such as mobile phones, computers, and televisions, are turned off, any potential ambient light sources in the area are eliminated. That will help establish a dark environment that is conducive to having a good night's sleep and will contribute to the formation of the domain. It will also assist in producing an environment that is conducive to getting a good night's sleep.
  • Taking a bath with Epsom salt or essential oil of lavender is a great way to wind down and get ready for sleep because it has a calming and relaxing impact on the body. That is an excellent method to get ready for sleep as well. Your ability to get a good night's sleep won't be disrupted as much as a result of this.
  • Get up early: If you want to manage your sleep patterns better and improve the quality of your sleep over time, you should try waking up at the same time every day and avoiding oversleeping. If you do this consistently and don't sleep too much, you will improve your sleep quality. If you decide to go through with it, you have to make sure that you give yourself enough time to sleep each night.

Make Sure You Are Eating Enough Fat (And Carbs)

Make Sure You Are Eating Enough Fat (And Carbs)

Make Sure You Are Eating Enough Fat (And Carbs)

If you are transitioning to a very low-carb diet, it is conceivable that you will feel substantial demands for foods and beverages that are not permitted on the ketogenic diet. If this happens to you, it is essential to remember that these cravings are usual and that they will pass. This category includes a wide variety of meals, some examples of which are included below: cookies, bread, spaghetti, and bagels.

On the other hand, adhering to a ketogenic diet and ensuring that your body gets an adequate amount of fat, which is the primary fuel for the ketogenic diet, will help you fight cravings and keep you from feeling hungry. That is because fat is the ketogenic diet's primary energy source, and this is because fat is used in the ketogenic diet as its primary fuel source.

According to several studies, following a diet low in carbohydrates can assist in lowering the desire for foods rich in carbohydrates and sweets. One can feel less of this need if one adheres to a diet low in carbohydrates.

People who find it challenging to adapt to the ketogenic diet may discover that cutting back on carbohydrates over a more extended period rather than eliminating them entirely all at once is more beneficial. That is because cutting back on carbohydrates over an extended period also makes it easier to maintain the ketogenic state. That is because reducing the number of carbs consumed can gradually affect blood sugar levels.

It is possible that gradually reducing the number of carbohydrates you consume while simultaneously increasing the amount of fat and protein in your diet can help the transition go more smoothly and reduce the severity of keto flu symptoms.


Maintaining adequate hydration, replacing any electrolytes you may have lost, refraining from engaging in strenuous activity, getting sufficient sleep, and ensuring good fat consumption. And gradually reducing the number of carbohydrates consumed over time is essential to an effective defense against the keto flu.

Why Do Some People Get The Keto Flu?

Keto Flu Symptoms

Keto Flu Symptoms

People have varying degrees of success in adapting to ketogenic diets—coming off of sugar alcohols, and it comes more naturally to some people than others. Others might be able to adjust to the new diet without experiencing any unpleasant side effects, while others might suffer from symptoms of the keto flu for several weeks at a time.

How an individual's body adjusts to changes in the fuel supply for their metabolism is related to the symptoms that the individual feels.

In almost every instance, the entry of glucose into the bloodstream directly results from the digestion and absorption of carbohydrates. In turn, glucose provides the body with a source of energy that it can use.

When carbohydrates are consumed in significantly lower quantities, the body's metabolism shifts to one that produces ketones from fat rather than glucose. Ketones are a byproduct of this transformation, and this happens because fat serves as a more reliable source of fuel than glucose does.

People who consume a high volume of carbs regularly, particularly refined carbohydrates such as pasta, sugary cereal, and soda, may have a more challenging time transitioning to a ketogenic diet. That is because ketogenic diets are higher in fat and lower in carbohydrates. And that is because ketogenic diets have higher grease and reduced carbohydrate content than regular diets.

Because of this, transitioning to a diet high in fat and containing a minimal amount of carbohydrates may be difficult for some people, while other people can switch between fuel sources with relative ease and experience very few or no symptoms of the keto flu at all. As a result, the ketogenic diet may be challenging for some people, while others can easily switch between fuel sources.

Even though the reasons why some people have an easier time transitioning to ketogenic diets than others are not entirely understood, it is generally acknowledged that genetics, electrolyte loss, dehydration, and withdrawal from the consumption of carbohydrates are the primary causes of the keto flu.

How Long Will It Last?

Keto Flu Symptoms

Keto Flu Symptoms

Thankfully, for most people, the unpleasant symptoms of the keto flu only last for about a week at the very most at most end of the spectrum.

On the other side, due to the significant amount of fat that is included in the diet, specific individuals may have a more difficult time adjusting to the low-carbohydrate, high-fat eating plan that is being recommended.

These individuals will likely continue to experience symptoms for at least one more full calendar month, possibly for as long as two or three months.

Your body will eventually become accustomed to producing energy from ketones, and as a result, these symptoms will finally start to fade away. That is because your body will eventually become acclimated to the ketogenic diet. That is because, after some time, your body will acquire acclimated to derive its energy from ketones.

Suppose you are feeling extraordinarily unwell and experiencing symptoms such as persistent diarrhea, fever, or vomiting. In that case, making an appointment with your primary care physician is in your best interest. Your doctor will be able to eliminate other potential causes of your ailment thanks to the information you provide. When switching to a ketogenic diet, many people report having symptoms that are commonly referred to as the "keto flu." On the other hand, if you are feeling particularly ill and exhibiting these symptoms, you should make an appointment with a qualified medical practitioner as soon as you possibly can.


Certain persons are more likely to encounter the symptoms of keto flu than there are others. These symptoms may be brought on by a variety of factors, such as heredity, the loss of electrolytes, dehydration, or an abrupt cessation of the consumption of carbs. Even though the symptoms of the keto flu typically disappear after a week, there is a chance that some people will continue to experience them for more than a month. That is especially true if they are severe.

Who Should Avoid Ketogenic Diets?

Keto Flu Symptoms

Keto Flu Symptoms

The ketogenic diet has the potential to be helpful for a substantial number of people; however, it is not appropriate for all individuals.

Pregnant or breastfeeding women, adolescents, and teenagers should probably not follow the ketogenic diet unless the diet is being used therapeutically and supervised by a physician. An exception to this rule would be if the diet is being used to treat epilepsy and the patient is under the care of a physician. If the diet is being used to treat epilepsy, the exception is that people in these age categories should adhere to the diet; otherwise, you should not follow this rule.

In addition, people who have particular health issues, such as renal illness, liver disease, or illnesses that affect the pancreas, are not permitted to follow this diet and should avoid it at all costs if they want to preserve their health.

In addition, people with diabetes considering adopting a ketogenic eating plan should confer with their primary care physician before moving forward with their projects. That will make it possible for the primary care physician to decide whether or not it is safe for people with diabetes to adhere to this kind of diet and whether or not it will satisfy the particular requirements of the person with diabetes.

Individuals who have a hypersensitivity to the cholesterol that is swallowed via their food may discover that following this diet is not an option that is suitable for them. That is not the least important consideration. This condition affects around one-quarter of the world's entire population in some manner.


It is possible that pregnant women, children, people with kidney, liver, or pancreatic disease, and those who are sensitive to the cholesterol in their diet should not follow the ketogenic diet. Additionally, those susceptible to the cholesterol in their diet should not follow the ketogenic diet. Additionally, individuals hypersensitive to the cholesterol present in their diet are not good candidates for the ketogenic diet.

The Bottom Line

Keto Flu Symptoms

Keto Flu Symptoms

The term "keto flu" refers to symptoms that may develop due to the body adjusting to a ketogenic diet. These symptoms may include headaches, body aches, and fatigue. These symptoms may include fatigue, aches and pains all over the body, and headaches.

When switching to a diet that is high in fat and low in carbohydrates, it is not unheard of for some people to experience symptoms such as nausea, constipation, headaches, tiredness, and cravings for sugar. However, it is essential to note that these side effects are not expected, and this is because it takes longer for the body to metabolize fats and proteins than it does carbohydrates.

It is possible to lessen the severity of the keto flu symptoms by ensuring that your diet contains an adequate balance of fat and carbohydrates. It is getting proper rest, maintaining a sufficient hydration level, and replacing any electrolytes that may have been lost while on the ketogenic diet. Getting adequate rest, maintaining a proper hydration level, and replacing any electrolytes that may have been lost while on the ketogenic diet.

Frequently Asked Questions

What are the symptoms of keto flu?

After starting a ketogenic diet, some people report experiencing symptoms dubbed the "keto flu." These symptoms can appear between two and seven days after starting the diet. This condition, which is not recognized by medicine, can present itself in many ways, including headaches, brain fog, tiredness, irritability, nausea, difficulty sleeping, and constipation, to name just a few of the symptoms you can experience.

What does keto flu mean?

On the other hand, having symptoms of the keto flu does not necessarily suggest that you are in the metabolic state of ketosis; rather, it indicates that your body is reorganizing how it metabolizes food to generate energy. Ketosis is a metabolic state when your body breaks down fats and converts them into ketones. You have not yet entered nutritional ketosis until your body has produced an adequate quantity of ketones for them to supplant glucose as the primary source of fuel for your organs and muscles. Until this point, you have not yet achieved nutritional ketosis.

How can you treat keto flu quickly?

For an effective defense against the keto flu, it is essential to maintain adequate hydration, replace any electrolytes that may have been lost, refrain from engaging in strenuous activity, get a sufficient amount of sleep, ensure good fat consumption, and gradually reduce the number of carbohydrates consumed over time.

What is the duration of keto flu?

The keto flu is a temporary condition that, in most people, goes away within a week or two of starting a ketogenic diet. That can be expected to be the case. Suppose your symptoms of keto flu last for more than ten days. In that case, if they are physically uncomfortable or if they render you unable to function normally, you may wish to seek the advice of a qualified medical practitioner.

How can a keto diet cause me to feel so sick?

The keto flu can bring several unpleasant side effects, such as nausea, vomiting, headaches, and tiredness. These symptoms appear as the body adjusts to operating with a lower amount of carbohydrates and moves into a state of ketosis, which is the metabolic condition resulting from eating fewer carbohydrates. Transitory imbalances bring on symptoms in the body's mineral levels, insulin levels, and energy sources. These imbalances can also bring on symptoms.