How to Survive the Keto Flu

Keto Food Pyramid

What is Keto Flu?

The keto flu is a side effect of switching to a low-carb diet. Not every Ketonian experiences the keto flu, but many do. It is crucial to be familiar with the keto flu before engaging in the keto dietary change to mitigate the chances of throwing in the towel. Also regarded as the ‘carb flu,’ it is a result of the body adapting to the keto diet, or any diet consisting of low carbohydrate intake.

It is typically experienced after the first few days of making the switch to keto, and it usually lasts for about one week, though some people report enduring the keto flu for about one month. This disparity would be a result of the person’s prior diet – if they were eating tons of carbs before the switch, it would be more severe. Take note, however, that not everyone experiences the keto flu, a phenomenon still undergoing research.

This unpleasant side effect of beginning the keto diet is a collection of flu-like symptoms caused by changes in the body’s metabolism and the limited consumption of carbohydrates1. The switch to keto triggers the burning of ketones in place of glucose for energy – a process called ketosis.

Mitigating Negative Side Effects of Ketosis

It is an excellent idea to be aware of the keto flu before engaging in the keto diet or any other form of low-carb diet because the keto flu is the primary source of failure or remission from practicing these extreme diets. Furthermore, it is essential to remember that these are natural side effects and will not last forever – usually only around one week.

There are still some proactive methods of fighting the keto flu and mitigating the unpleasant and adverse side effects. Taking a proactive approach to enduring the keto flu is imperative for success in the diet and in your overall health and wellness goals. Like the actual annual influenza, there is no one shot cure. Instead, the most effective approach is to understand what is happening and why, as well as taking steps to lessen the negative symptoms.

Progressively Reduce Carb Intake

One of the biggest causes of intense keto flu symptoms is switching from a regular diet to low-carbs overnight. Like any momentous change in the body, it is vital to do it over time to allow the body to adjust to the changes. If done with too much haste, symptoms of keto flu will worsen. This effect is like that of withdrawal from a drug, but in this case, from carbs.


Stay Hydrated

Staying hydrated is essential for overall good health. While starting into the keto diet, it is necessary to be aware of your hydration level as keto causes rapid water loss because of the decreased absorption of sodium that stores water inside the body. Make sure to drink plenty of water throughout the day and replace all water lost through sweat during exercise. Hydration will help reduce the fatigue and muscle cramping experienced during the beginning stages of the keto diet.

Replace Electrolytes

Electrolytes are minerals within the body that are essential in balancing the body’s water levels and pH (Acid/Base) levels. They are abundant in many of the leafy greens called for in the keto diet, but your body may be deficient during the transition to keto because of the lack of fruits and other electrolyte-rich foods. Not only will replacing electrolytes with foods high in Potassium and Magnesium aid in staying hydrated, but it will further aid in reducing muscle cramps, sleep difficulties, and headaches2.

Avoid Heavy Exercise

Avoiding heavy exercise is indispensable in overcoming the keto flu because it puts extra strain on the body. This strain compounds with the ‘behind-the-scenes’ stress your body is fighting during the transition and will worsen keto flu symptoms. That is not to say that avoiding all exercise is a good idea. Light exercise is excellent and recommended as it aids in the transition and is beneficial psychologically. A good mood is essential to success in the transition to the keto diet.

Get good sleep

Good sleep is essential for optimal functioning in all aspects of life; be it Jiu-Jitsu, work, or socializing. Bad sleep habits worsen the effects of the keto flu because they negatively affect your mood by increasing cortisol concentrations in the body. Some steps that may foster good sleep habits would be reducing caffeine intake, reducing ambient lighting, waking up early, and taking a bath before bedtime3.

Tracking Ketosis

Ketosis is the result of successfully transitioning to the keto diet and usually begins 3 to 4 days after starting the keto diet or consuming fewer than 50 grams of carbohydrates per day. It is a good indicator of progress in the keto diet, and there are several ways to know if ketosis has begun in your body and measuring it.

  1. The most exact test of ketosis is a blood test. Blood tests often tend to be costly and difficult to get. A company name KetoMojo fixed this problem. They supply Ketonians with a Ketone and Blood Glucose Monitoring System that measures its user’s Glucose Ketone Index (GKI). The GKI is an excellent biomarker of metabolic health and wellness. With its low pricing and host of benefits and features, KetoMojo is a superb choice for anyone needing to measure ketone concentrations accurately and quickly. Check out their website here for more information on their products.
  2. Other products offered for testing ketosis levels are Ketostix, or ketone urine testing strips. These are cheap litmus-test like test strips that get dipped into the urine to test how ‘deep’ in ketosis you are. Though the concentration of ketones in the urine is different from that of ketones in the blood, it is still remarkably accurate.
  3. The cheapest objective measure of ketosis is to breathe. Initiating into the keto diet often results in ‘keto breath’ – a fruity or metallic smell. Keto breath, caused by the burning of ketones for energy, is perfectly natural and healthy. It diminishes quickly over time and fades entirely after a few weeks.

The keto diet is not the easiest thing to master, but with enough time and effort, you will see stunning results. If you suffer from the keto flu for an irregular length of time or have complex or severe symptoms visit your doctor at once as this may indicate underlying health issues needing immediate treatment. Good luck on your journey to a healthier, keto-fueled life and make sure to share your story with us here on the Livermore Supply Co. Blog.

If you want to find our more about my personal experience, please review the related articles below. In addition, I highly Recommend Keto Resources, without the information their my experience with Keto wouldn't have been as good.


1. Paoli, Antonio, et al. “Ketosis, Ketogenic Diet and Food Intake Control: A Complex Relationship.” Frontiers in Psychology, vol. 6, Feb. 2015. PubMed Central, doi:10.3389/fpsyg.2015.00027.

2. Gröber, Uwe, et al. “Magnesium in Prevention and Therapy.” Nutrients, vol. 7, no. 9, Sept. 2015, pp. 8199–226. PubMed Central, doi:10.3390/nu7095388.

3. Song, Hong-Tao, et al. “Effects of Sleep Deprivation on Serum Cortisol Level and Mental Health in Servicemen.” International Journal of Psychophysiology: Official Journal of the International Organization of Psychophysiology, vol. 96, no. 3, June 2015, pp. 169–75. PubMed, doi:10.1016/j.ijpsycho.2015.04.008.


Thomas Grylka

Thomas is a recent college graduate and a content writer for the Jiu-Jitsu Times. He earned his brown belt in Wa Shin Ryu Jujutsu under Gregory M. Kane during his time as a student at UConn.

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