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Keto Flu – definition, side effects, and quick remedies

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So, you’re thinking of starting the Keto Diet.

But, you’ve heard about this awful thing called the Keto Flu.

Is it similar to Covid? Is it bacteria-related? Should I call the hospital?

Thankfully, the Keto flu is temporary, is not contagious, and it’s easily quashed!

Keep reading to learn more about the Keto flu, other side effects on the keto diet, and quick remedies to have you feeling like yourself in no time!

woman with headache reading a book

Keto Flu Definition

When a person starts on the keto diet they reduce their carbohydrate intake to fewer than 50 grams per day.

Normally, the average person eats approximately 200-300 grams per day.

However, when the body doesn’t get enough carbs for energy, the liver starts to produce glucose for energy and uses it’s stores.

Also, your body then starts to breakdown fatty acids, which produces ketones in a process called ketogenesis.

This is when the body tissues use ketones as fuel, and the body enters a state of ketosis.

Additionally, insulin is involved in transporting glucose to the brain.

The lack of carbohydrates decreases the amount of insulin in the bloodstream.

As a result, people may experience increases in sodium, potassium, and water that is released in the urine, which may cause dehydration.

Likewise, insulin is involved in transporting glucose to the brain.

And, before the brain starts to use ketones for energy, it will have less fuel.

These changes will occur for about the first 3 days of the keto diet before blood sugar returns to regular levels.

This loss of water and sodium is responsible for many of the unpleasant symptoms of keto flu.

Keto flu symptoms woman with abdominal cramps

Keto Flu Symptoms

A person’s response to starting the keto diet are very individual.

Some people may feel slightly tired for a few days after starting keto.

Conversely, some may develop symptoms that strongly impact their ability to function for several days.

These are the most common symptoms of the keto flu:

  • Brain fog or difficulty focusing
  • Dizziness
  • Fatigue
  • Headaches
  • Irritability
  • Lack of motivation
  • Muscle cramps
  • Nausea
  • Sugar cravings

Most Common Keto Diet Side Effects

The most common side effects that are experienced when restricting carbohydrates are:

  • Headache
  • Bad breath
  • Weakness
  • Fatigue
  • Constipation or diarrhea

Even though some people do get these side effects when starting the keto diet, the weight loss that happens because of these rapid changes is usually welcomed!

woman drinking water on Keto diet

Keto Flu Quick Remedies

Even if you feel bad, there are ways to reduce symptoms and help your body get through the transition period more easily.

1. Increase salt and water intake

This is the number one tip – maintain hydration and feel better fast.

When keto flu symptoms start, drink a glass of water with half a teaspoon of salt stirred into it.

This one action may alleviate your keto flu symptoms within 30 minutes. 

Drinking lots of water and maintaining your electrolyte levels is necessary for optimal health and reducing symptoms.

2. Avoid strenuous exercise

Any strenuous exercise should be avoided if you experience keto flu symptoms.

This can include fatigue, stomach discomfort, headaches, and muscle cramps.

If these symptoms occur, it may be time to give your body a rest.

However, light activities like yoga, walking, and leisure biking may improve your symptoms.

Keto flu symptoms get enough sleep

3. Get enough sleep

Another complaint from people adapting to the keto diet are fatigue and irritability.

If you are not getting enough sleep, cortisol levels rise in your body and can negatively impact your mood.

Additionally, a lack of sleep can make keto flu symptoms worse.

Try these tips if you are having a difficult time falling asleep:

  • Take a warm bath with epsom salt or essential oils
  • Reduce caffeine – make sure you cut-off caffeine at least four hours before bedtime.
  • Decrease ambient light – limit the use of cell phones, tablets, and tv’s in the bedroom to promote more restful sleep.
  • Turn down the temperature a few degrees to create a cooler sleeping environment.
  • Maintain sleep patterns – wake up at the same time every day so your body gets used to this and sleep quality improves.

4. Maintain electrolytes

Getting enough important nutrients is crucial in powering through the adaptation period of the keto diet.

As we said before, salting food and increasing salty broth are beneficial.

Additionally, including potassium-rich foods like avocados and green leafy vegetables can ensure you maintain a healthy balance of electrolytes.

Also, eating spinach, almonds, quinoa, and pumpkin seeds can help reduce muscle cramps and headaches.

5. Eat enough Fat and Carbs

When you first start the keto diet, your body may crave foods that you are not supposed to eat (like sweets).

But, eating enough fat will help decrease these cravings and keep you feeling satisfied.

Also, you may have to eliminate carbs gradually, rather than all at once.

Finally, slowly cutting back the carbs, while increasing fat and protein, may make your transition smoother and reduce keto flu symptoms.

women working out

Keto Flu takeaway

As shown above, the Keto Flu is a group of symptoms associated with how your body adapts to a ketogenic diet.

Many symptoms, such as headaches, fatigue, nausea, muscle cramps, and sugar cravings are common when adapting to low-carb diet changes.

So, to avoid keto flu side effects, be sure to stay hydrated, replace electrolytes, get plenty of rest, and continue to eat the right

amount of fats and carbohydrates on the ketogenic diet.

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