Keto flu or Low-carb flu explained and 8 ways to crush it

Ketosis is like a cold were awake before it, but not as awake as you are after it. It's like that shot of adrenaline when someone scares the shit out of you, but it lasts for hours. It's like that time Aladin sang "A whole new world, dont you dare close your eyes!" because you're woke AF.

Its pretty nice. But I’ll be real with you, this is the crappiest part of the ketogenic diet. It sucks and it’s the reason most fail at low carb. It takes no prisoners. You either make it through adaptation, or you surrender to sugar burning. You can't avoid it. But, there are tricks to dull the symptoms. I’ll share them with you so you don’t waste months in pain, like I did.

I began the ketogenic diet about 5 years ago, when it was still fringe. There was no coaching or online guides. No instruction manual. I had to trust the science and wing it. It was brutal. I considered medical attention. Friends and family were worried…it was horribly awesome.

Since then I've learned a few things. Through coaching and self-experimentation I’ve ironed out a plan of attack.  

What is it?

The keto flu or low-carb flu is what happens when we stop eating sugar and carbs. The goal is to force the body into fat burning mode (the holy grail of health). If you’re a lifelong sugar burner, your body doesn't understand that it has a second fuel source…fat.

When restricting carbohydrate, the body throws a shit fit. It does everything in its power to obtain its fuel source, carbohydrate. It literally thinks it’s going to die.

Symptoms: Intense cravings for carbohydrate and sugar (like crackhead status), fatigue, lightheadedness, headache, dizziness, body aches, dry mouth, demotivation, agitation, poor sleep, nausea and even anxiety. I experienced them all. So worth it.

Duration depends on how fast your body can become fat adapted. Fat adaptation is the ability to burn fat for fuel rather than carbohydrate/sugar. This is the whole point of keto and low carb.

Complete fat adaptation is about 3 -4 weeks, but the flu part is only about 3-7 days. Some clients cruise right through it, others swear they're dying. Everyone is different. Women tend to have a harder time.

You use different energy systems to burn fat. It takes time to build those systems up. This is a process called mitochondrial biogenesis, a fancy way of saying you will grow more mitochondria. Mitochondria are the organelles within your cells that make energy from fat. They are your miniature power generators and during fat adaptation they increase in density throughout your body. In addition, each and every mitochondria will become stronger. Consider this Beast Mode activation.

Think of your body as a power plant. On sugar, you were a coal burning plant. Inefficient and bad for the environment…non-renewable. On fat, you’re a solar plant. Efficient, clean and renewable. It takes time to remove outdated coal furnaces and install state of the art solar panels.

That’s what’s going on inside your cells. A total system upgrade. You’re literally growing new machinery to burn fat.

Don’t Give Up

You're going to feel like shit, and your cravings are going to be gnarly. It's important you don’t give up. Splurging on donuts, bread, pasta or cookies will interrupt adaptation. Only after you deplete your glycogen (stored carbohydrate) does the body begin burning fat. We deplete glycogen by not eating more of eventaly runs out.

Caving into cravings and eating more carbohydrate/sugar before glycogen is sufficiently depleted will replenish glycogen stores, delaying fat burning. Make sense? We must force the body into fat burning mode via carb restriction. 

Think of it this way. Imagine you're a hybrid car. Your goal is driving on electricity and only way is to completely run out of gasoline. If you keep adding gasoline to the tank when you're low on fuel you will never succeed in running on electricity.  

These are new concepts to most people. We've been told we need carbohydrate. Not true. If this is confusing, and you'd like to learn more, schedule a free 10 minute coaching call. Hit us up in the comments below.

Moving on!

Keto Flu Problems

1.       Not eating enough fat

2.       Not eating enough total calories

3.       Not consuming enough salts/electrolytes

4.       Exercising too hard

5.       Not getting enough sleep

6.       Dehydration

7.       Toxins released from fat

8.       Total carb restriction

How to fix it

1.       Eat more fat, a lot more. You have removed your primary fuel source (carbohydrate), replace it with fat. The amount of protein you eat should remain the same, it is not a fuel source. It will not replace the energy lost from carb restriction. Don’t be afraid to cover everything you eat with fat. Grass-fed butter, coconut oil, olive oil, heavy whipping cream, full fat cheeses, organic lard and most importantly a high quality MCT oil. Once you make it through the keto flu, you can throttle back on the fat intake, but for now, use fat to displace the missing carb. 

2.       Eat more total calories. During fat adaptation increase whole, low carb foods. Splurge on eggs, meat, poultry, fish nuts, seeds, cheeses, creams, vegetables and low sugar fruit. Your total calories decrease with carb restriction, be sure to replace them with the good stuff. This is your hall pass to pig out.

3.       On low carb we pee out large amounts of salts and electrolytes. Often this causes cramping. Add them back in by salting your food and water. Err on the side of too much rather than not enough. Be sure to use high quality real salts like pink Himalayan or Celtic sea salts. Electrolyte tablets with magnesium and potassium are a good idea. Warm epsom salt baths are the most effective way to get magnesium in you. They sooth aches and are great for sleep too. Take a few. 

4.       High intensity exercise uses glycogen for energy. Remember, low glycogen stores are the reason you feel like shit. We want to depplete glycogen but during the keto flu this might not be the best method. Plus, it wil intensify cravings. Instead, exercise in a way that utilizes fat for fuel. This will jump start your fat burning mode. To burn fat during exercise, use the 180 formula created by Dr. Phil Maffetone. It's simple, take 180 and subtract your age to get your target heart rate. I’m 31 years old, so my 180 method is: 180 – 31 = 149.

5.       This is huge. Get to bed early. Your cells have work to do and they do most of it during deep sleep.

6.       Stay hydrated but don't overhydrate. Drink only when thirsty and add some salt to your water. Drinking too much will flush more of those vital salts and electrolytes out. This is a common mistake I see. More is not better. Thirst is the perfect indicator.

7.       Going low carb releases toxins from stored body fat. Specifically an inflammatory molecule called arachidonic acid that causes headaches. Eating fatty fish or taking a fish oil supplement rich in anti-inflammatory omega 3 fats could counteract the inflammation caused by the released toxins. Grub on some sardines, salmon or cod liver oil. This is just a good idea regardless of keto flu. 

8.       It’s called low-carb not no-carb. Pile on the non-starchy veggies like Brussel sprouts and broccoli. Have a little dark berries. If the keto-flu symptoms are becoming too difficult, your last defense can be adding in some good carbs. Dont go for the donuts though. Choose lower glycemic carbohydrates with no added sugar. And limit them so small portions. 

Bonus Hacks:

1.       L- Carnitine helps shuttle fatty acids into mitochondria for conversion into energy. That’s the whole point of fat burning. L-Carnitine can be made from amino acids in red meat so why not load up on steaks? You can also try a L-Carnitine supplement. 

2.       Drink bone broth. It's an amazing superfood and contains a lot of salt, water, calories and fat. It hits 4 of the 8 tips above. Here's a recipe, but all you really need is bones, water and a crock pot. 

A word on Supplemental Ketones

Taking ketones during fat adaptation is like having a bad spotter when lifting weights. The guy who does the work for you. To get strong, you need to lift that weight. You need to force the adaptation to the body.

Every ketone you eat is a ketone you aren't making yourself. The whole point of the ketogenic diet is making your own ketones from body fat. If you’re eating them, you’re body isn’t burning fat to make them.

Exogenous ketones do have their place within a ketogenic diet, but many people continue to eat poorly and just add in ketone packets. Taking ketones is not a ketogenic diet…but that’s for another post.


The Keto-Flu is a bitch. Especially if you’re a lifelong sugar burner. But it’s so worth it. Becoming fat adapted is like upgrading to YOU version 2.0. Until you experience ketosis there’s really no way of describing it. Its like that first cup of coffee in the morning. The one that causes you to singing like Mariah Carey in your car, or to send positive text messages to friends. But ketosis lasts all day. It’s a shame how many of my friends and family give up because they can’t hack the sugar cravings.  If this is your first time attempting low carb, stick with it. And if you slip up, get back on the horse the following day. Use these tools above before you throw in the towel.

The best way to beat the keto flu is hiring a coach. If you need help designing your meals, shopping, selecting supplements, designing an exercise program, making bone broth or whatever, hit me up. let’s do this!

Thanks for reading