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Complete Survival Guide to the Keto Flu: 1. What is the Keto Flu and 2. How do you Get Through it?
What is the Keto flu?
Posted on Nov 12, 2020

What is the Keto Flu?


If you’ve researched the Keto Diet, then you’ve definitely read or heard about the most common side effect – the keto flu.  With the rising popularity of the Keto Diet, many people are finding themselves interested in learning about how to get started on the Keto diet, or which type of keto diet would work for them.  The basics of the keto diet is keeping carbs low, less than 50g/day, increasing healthy fat intake, and reaching a daily protein goal.  Simple!  


But then there is a dreaded side effect people hear about called The Keto Flu…. I get it!  Any term with FLU in it must be terrible right?  Don’t worry!  It isn’t as bad as it sounds, and the good news is that it can be totally avoidable!


So, what exactly is the Keto Flu?


The Keto Flu (https://www.health.harvard.edu/blog/what-is-keto-flu-2018101815052) usually occurs in the beginning of the keto diet journey when you have restricted your carbohydrate intake below a certain level, 50g/day or less, and your body is going through withdrawal from glucose and carbohydrates.  It takes the body a period of time to switch from using carbs and sugar for fuel and using ketones and fat instead.  


Symptoms of the Keto Flu


As your body adjusts from being a sugar burning to a fat burner, you may experience some of the following symptoms associated with the Keto Flu:

  • Dizziness, lightheaded
  • Drowsiness, fatigue
  • Headaches
  • Muscle cramps or weakness
  • Sugar and carb cravings
  • Insomnia
  • Irritability
  • Nausea


The good news is, not everyone will experience all these symptoms and there are ways to avoid them.  


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How to Avoid the Keto Flu


While your body is figuring out how to adjust to this new carb restricted diet, you can help avoid the Keto Flu symptoms by making a few simple adjustments to your daily routine:


  • Stay Hydrated – Staying hydrated is always important.  Set your goal for at least 72 oz of water each day.


  • Increase Electrolytes – your electrolytes may become imbalanced as you decrease the amount of carbohydrates you eat.  This is due to your kidneys excreting more water and along with it, sodium.  You could purchase an Electrolyte supplement, or you could make your own using Potassium Chloride Powder, Epsom salt (pure magnesium sulfate), and Sodium Bicarbonate.


  • Take a Magnesium Supplement – Magnesium helps support a healthy immune system, builds healthy bones and prevents muscle cramping.  A good tip is to take a Magnesium supplement of at least 500 mg per day.  Be sure it is Magnesium Glycinate for maximum absorption.


  • Try Exogenous Ketones – Exogenous Ketones can put your body into a state of Ketosis in less than 60 minutes.  This can help ease the discomfort of the Keto Flu.


  • Exercise – a good sweat can help burn through the stored glucose stores faster than a normal resting rate.  This can help you get through those stored carbs and get to the lean mean fat burning machine you want to become.


How to Treat the Keto Flu


Treating the symptoms of the Keto Flu is much like avoiding it.  The most common cause of the Keto Flu is an electrolyte imbalance.  This imbalance can be the reason behind cramping, dizziness, fatigue and headaches.  


Taking an electrolyte supplement, as described above, in combination with a Magnesium supplement, will go a long way in reducing or eliminating the Keto Flu symptoms altogether.  


Additionally, Exogenous Ketones really can help minimize the effects of Keto Flu and help you start feeling the many benefits of Keto in a short time; happy, energetic and focused.


How long does Keto Flu last, does it happen all the time, and is it dangerous?


How long the Keto Flu lasts, will it definitely happen to me, and is the Keto Flu dangerous are common questions we get asked all the time by our clients.  


The truth is, it may not happen to everyone who starts a keto diet and not everyone will experience the same symptoms of the Keto Flu.  This is because everyone is different.  When we list the different symptoms of the Keto Flu, these are the most common experienced by many different people.  I know when I started keto, way back in the beginning, my most common side effects were lightheadedness when I stood up and of course, sugar and carb cravings.  


In the beginning, typically someone starting full force and committed to the Keto Diet, restricting their carb intake right away, could almost immediately start feeling symptoms of the Keto Flu within 2-3 days.  Usually these symptoms will reside within a week.  Using the tips in this article can greatly decrease your chances of experiencing the Keto Flu or avoid it completely.


Here’s the thing.  Just don’t give up!  You see people all the time say, ‘I tried Keto for a week and I felt terrible.’  Well chances are they dove in headfirst without any preparation, probably didn’t know much about carbohydrate and sugar withdraw and just gave up saying Keto isn’t for them.  


On the Keto Diet, your body doesn’t change overnight.  It takes time for your body to adjust to a new fuel source.  More like 6-12 weeks to become fully Keto Adapted.  But the Keto Flu will not last nearly as long.  Take the time on how to prepare yourself for starting a keto diet.  Mental preparation is key!  Stay strong!  Good things are about to happen, and your body will thank you!


The most important step to being successful on the Keto Diet is to first – change your mindset


Is the Keto Flu Dangerous?


Experiencing the Keto Flu certainly is not dangerous.  It is simply a metabolic shift your body is trying to learn and get used to while it switches from being a carbohydrate and sugar burner to a lean mean fat burning machine and using Ketones for fuel.  


When your body uses ketones for fuel and is in a state of Ketosis, this is when it will start burning fat for fuel.  However, do not confuse Ketosis with Ketoacidosis.  


Ketosis is a metabolic state of the body where you are burning Ketones for fuel.  Ketoacidosis is a dangerous condition, typically in diabetics, where your insulin is so low that sugar in your body is not being absorbed by the cells and used for fuel.  A build up of Ketones in the blood will cause it to become acid and is potentially life threatening.  (https://medlineplus.gov/ency/article/000320.htm)


Ketosis and Ketoacidosis are NOT the same thing and ketosis does not cause Ketoacidosis.  


I’ve tried Keto before and want to do it again.  Will I still get the Keto Flu?


The short answer is – everyone is different, and everyone may experience the Keto Flu differently.  


If you were on the Keto Diet for a long enough time where your body made the shift from burning glucose to burning fat, chances are you are more metabolically flexible.  See our post that explains the differences between Keto-Adapted vs Fat-Adapted to understand metabolic flexibility in more detail.


That being said, if you’ve done keto and were successful but then stopped for a period of time but now want to go back on, chances are the Keto Flu won’t bother you as much as it did the first time.  You may still experience a few symptoms such as fatigue or a bit of energy loss, but they won’t be as bad.  This is because your body will remember.  Your body will remember what it is like to live and function without carbohydrates as its primary fuel source.


Let’s Go KETO!


OK!  So, there it is.  Your complete guide to all things Keto Flu.  Just remember, the Keto Flu is easy to avoid, easy to treat and best of all, does not last time.  Stick to your Keto Diet and in no time, you will be experiencing all the benefits of Keto and none of the initial side effects. 

For help with the Keto flu, reach out to us at HoleKeto (www.holeketo.com).  We have many great coaching options to assist you on your Keto journey.

Holly Ambris-Certified Keto Coach