Learn how to kick the keto flu. These tips will help you through the crummy transition from sugar burner to fat burner. Read more.

What is The Keto Flu and How Do You Kick It?

When you are kicking the sugar habit your body is going to be flushing out toxins and switching its processes. This process might leave you feeling a little under the weather. It feels very much like the flu. Thus the name: Keto Flu.

All the same symptoms: fatigue, nausea, headaches, body aches and even a mild fever can pop up in the first 2 or 3 days and last up to a couple of weeks.

Once the body is adapted to burning fat and fully in ketosis, the symptoms usually fade away.

The one exception to this might be headaches. These continue to plague you if you have an electrolyte imbalance.

Why Does Keto Flu Happen?

The process of switching from being a carbohydrate (simple sugar) burner to a fat burner is a change in your metabolic process. Your ability to adapt can be dependent on your genetics as well as your previous lifestyle habits.

If you were a complete sugar fiend before going keto you can probably anticipate some severe flu symptoms. If you ate something close to a Paleo diet, making the switch to a Keto diet might not be as drastic and your body will adapt more quickly.

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Learn how to kick the keto flu. These tips will help you through the crummy transition from sugar burner to fat burner. Read more.

You are flushing water from your system.

When your insulin levels drop it tells your kidneys that you don’t need as much sodium. Your body uses water to process sodium so when this signal goes through, your body releases all that water. Not only are you releasing water you are releasing electrolytes and minerals.

Losing electrolytes and minerals is what leads to the flu-like symptoms. You might have cramping, aches, and pains, diarrhea or constipation (or it can alternate). Sounds pleasant, doesn’t it? Don’t worry. It passes.

Your Thyroid T3 Levels May Change.

Dietary carbohydrates influence your T3 levels. Changing your diet is going to change your production of certain hormones. Your body will level these out, but until it does, you will be a little under the weather.

Lower levels of thyroid hormones might leave you feeling a little foggy and weak. This will pass and you will soon say goodbye to brain fog!

At First, Your Cortisol Levels Increase

You have just changed your eating patterns and the fuel your body is used to processing. There is bound to be some internal stress. Your T3 is connected to your cortisol production (which is another hormone that your body produces). Fluctuating levels of T3 and a change in your metabolic system is putting your system under stress.

If you are feeling extra irritable or having an issue with sleeping well, you probably have an increased cortisol level. Your body will adjust and bring your levels back down to normal. Just be mindful of the fact that you might be a little touchy and try not chew anyone’s head off.

My first time entering ketosis I was a mess for about 2 days. I felt sorry for my husband and kids. Hiding in my room wasn’t an option so I tried to temper my attitude. Do what you can and drink some broth. It will be better soon!

Curing The Keto Flu

Treating the Keto Flu is fairly easy. I’d like to say you can completely avoid it, but that might not be the case. You can definitely minimize it. When the body is in ketosis it will be flushing electrolytes, this can leave you feeling under the weather.

Get More Fluids

Make sure to drink lots of water, take a multivitamin and make sure you are getting plenty of sodium and magnesium. These two minerals are vital electrolytes and you need to be incorporating them into your meals and drinks regularly.

You might be thinking that you already salt your food a little. That won’t cut it. You need to be drinking broth, adding potassium and salt to your water, and making smoothies with electrolytes to help you get balanced.


Use this smoothie to help you kick the keto flu. Read more to see what the keto flu is and how you can cure it.

Image credit to How to This and That.

Eat More Fat

Your body is adjusting to being a fat burner. Give it what it needs. This MCT oil is odorless and tasteless. You can mix it into smoothies, your morning coffee or tea, or use it to cook your eggs. Increasing your fat intake will help your body adjust.

Make fat bombs and snack on them when you need to increase your fat macros.

Get Some Rest

Sleep is a great tool to help you succeed with the Ketogenic Lifestyle. It’s also a great way to survive the keto flu. Don’t push yourself too hard.

Take leisurely walks instead of kicking your own butt at the gym (your level of fatigue is going to seem higher at the gym). Do some yoga. You can still move and be moderately active. Just keep in mind that your body is already working really hard on the inside and cut it some slack, okay?

Check Your Carbs

I know the point of going keto is to limit your carbs. It’s possible that you went a little extreme and went from eating 80% of your daily calories as carbs to 2% (or somewhere in that range). That’s a considerable shock to your system.

One way to ease up on your keto flu is to add a few carbs back in. This isn’t an excuse to go order a caramel macchiato. Try adding in some natural carbs in that include some fiber.

Maybe a few apple slices and cheddar cheese. A half of banana and peanut butter.

Just bring your limit up closer to 50 or 100 grams for a day or two and then ease it back down again. It might make you feel loads better!

Kick the Keto Flu

Don’t let the idea of feeling puny for a few days scare you off from switching to a Keto Lifestyle. It really isn’t as terrible as it sounds (it’s still way better than the actual puking flu!!). And when you come out the other side you will be happy that you get to experience all the benefits of being keto!


Learn how to kick the keto flu. These tips will help you through the crummy transition from sugar burner to fat burner. Read more.

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