Keto Flu Vs. Cold: What's The Difference?

The keto flu is a natural reaction (almost like a feeling of withdrawal) the body undergoes when switching from burning glucose (sugar) as energy to burning fat instead. It is also known as the carb flu and is not the same as the actual flu. The keto flu does not include fever or respiratory symptoms like coughing or sneezing.

The keto flu typically lasts around 3-5 days but could drag on for 1-2 weeks for some individuals. Symptoms of the keto flu include fatigue, muscle cramps, headaches, dizziness, mental fog, poor focus and concentration, and difficulty falling asleep.

To reduce the symptoms of the keto flu, one can take an electrolyte supplement, drink plenty of water, eat more fat, take an exogenous ketone supplement, check carb consumption, exercise, and get plenty of restful sleep.

Keto flu is not an actual flu

Keto flu is a term used to describe the flu-like symptoms that people starting a low-carb, Paleo, or Ketogenic diet often experience. It is not an actual flu, but rather a set of side effects that occur when the body adjusts to a significant reduction in carbohydrate intake.

When you drastically cut down on carbs, your body goes through a transition period as it shifts from burning glucose (sugar) to burning fat for energy. This metabolic shift can cause various symptoms, such as fatigue, muscle cramps, headaches, dizziness, and mental fog. However, keto flu does not include fever or respiratory symptoms like coughing or sneezing.

The keto flu is typically mild and lasts for about 3-5 days, but it can sometimes persist for up to 2 weeks or even longer in some cases. The severity and duration of keto flu can depend on individual factors, such as genetics and metabolic resistance.

To manage keto flu symptoms, there are several strategies you can employ:

• Increase your fat intake by consuming fatty meats, adding butter and oils to your meals, and snacking on high-fat foods like cheese and nuts.
• Stay hydrated and replenish electrolytes by drinking plenty of water, bone broth, or mineral water, and considering electrolyte supplements.
• Avoid sweeteners and sugar-free treats, as they can confuse your system and trigger cravings.
• Get adequate rest and sleep, as fatigue is a common symptom during the transition.
• Take targeted supplements, such as exogenous ketones, to speed up the transition to ketosis and reduce symptoms.
• Gradually reduce your carb intake instead of cutting them out all at once, especially if you were consuming a high-carb diet previously.

While keto flu can be unpleasant, it is a normal part of the process when transitioning to a ketogenic diet. By following the strategies outlined above, you can mitigate the symptoms and make the transition smoother. Remember to listen to your body and adjust your diet accordingly.

Keto flu symptoms

The keto flu is a natural reaction (almost like a feeling of withdrawal) your body undergoes when switching from burning glucose (sugar) as energy to burning fat instead. The keto flu or carb flu describes the flu-like symptoms that people starting a low-carb, Paleo, or Ketogenic diet often experience.

Symptoms

• Poor focus and concentration
• Difficulty falling asleep
• Stomach irritability
• Fatigue
• Muscle cramps
• Headaches
• Dizziness
• Mental fog
• Sugar cravings
• Nausea
• Diarrhea
• Constipation
• Sore throat

The keto flu typically lasts around 3-5 days but could drag on for 1-2 weeks for some unfortunate individuals.

How to manage keto flu symptoms

• Take an electrolyte supplement
• Drink enough water
• Eat more fat
• Take an exogenous ketone supplement
• Check your carb consumption
• Exercise
• Get plenty of restful sleep

How to manage keto flu symptoms

The keto flu is not an actual flu but a term used to describe the flu-like symptoms that occur when transitioning into the metabolic state of ketosis. This is because the body has to adjust to using fat instead of glucose for fuel. Symptoms include fatigue, restlessness, brain fog, impaired coordination, muscle soreness, and stomach pain.

Focus on Alkalizing Foods

Eat foods that help to reduce inflammation, restore nutrient stores, and balance your body's pH level. These include fresh green vegetables, apple cider vinegar, and green drinks made from green vegetables and grasses in powder form. Limit caffeine and avoid sugary and alcoholic drinks, as well as inflammatory, processed foods.

Eat Enough Fat and Calories

Staying in ketosis requires getting about 80% of your daily calories from fat sources like coconut oil, olive oil, MCT oil, grass-fed butter, ghee, and fatty cuts of meat. Make sure you're eating enough fat, but not too much protein or carbs.

Drink Plenty of Water

The ketogenic diet causes a lot of water loss in the beginning, which can lead to dehydration. Aim for about four litres of water per day, but listen to your body and don't overdo it.

Consume Enough Salt and Prevent Electrolyte Imbalance

When you restrict carbohydrates, your body produces less insulin, causing your kidneys to flush out excess water and sodium. This can lead to an electrolyte imbalance, resulting in symptoms like weakness, cramps, headaches, and constipation. Consume bone broth, salted nuts, and pickles to replenish electrolytes.

Take Supplements

If you can't get enough electrolytes from food, consider taking supplements like magnesium glycinate or magnesium citrate.

Exercise (Gently)

Try less intense activities like yoga or walking, as these can help improve your body's ability to switch between burning fat and sugar for energy.

Get Enough Sleep

Make sleep a priority to help combat zapped energy levels. Aim for seven to nine hours of sleep every night and remove distractions before bedtime.

How long does keto flu last?

The keto flu is a group of symptoms reported by people starting a ketogenic diet, also known as the "keto" diet. It is very low in carbs but high in fat and protein. The intention is to put your body in a state of ketosis, where your body burns stored fat instead of stored glucose. Symptoms of keto flu can include:

• Stomach aches or pains
• Nausea
• Dizziness
• Sugar cravings
• Cramping
• Muscle soreness
• Irritability
• Diarrhea or constipation
• Trouble falling asleep or staying asleep
• Poor focus and concentration
• Headaches
• Brain fog

Symptoms of the keto flu generally begin within the first day or two of removing carbs from your diet. For most people, the keto flu lasts a week or less, but in extreme cases, it can last up to a month. Some people report symptoms of feeling weak lasting 3-5 weeks. If your keto flu symptoms last longer than ten days, or if they are actively painful or debilitating, you may want to consult a doctor.

Why keto flu happens

The keto flu is a natural reaction (almost like a feeling of withdrawal) your body undergoes when switching from burning glucose (sugar) as energy to burning fat instead. It is also known as the "low-carb flu" or "Atkins flu".

Your body is used to running on carbs. Cutting carbs in favour of fat is a huge change for your metabolism. So you don't switch over instantly. It takes a little bit of time to adjust.

This transition often causes temporary flu-like symptoms. Fatigue is the most common one, but you might also get muscle cramps, headaches, dizziness and mental fog.

Some of these symptoms are markers of sugar withdrawal. Sugar addiction is real and common, so trying to break away can be difficult. Others may be caused by a lack of certain nutrients, for example, electrolyte depletion or insufficient fat intake.

Your body wants carbs

If you’ve been eating a Standard American Diet (SAD) for a long time, then your body is used to eating over 200 grams of carbohydrates (often in the form of sugar) every day. And when you go Keto, you’re cutting that carb intake down to under 25 grams per day.

That means your body has to adjust. In particular, your body needs to stop relying on glucose for energy and switch instead to burning your fat stores. If you have been eating unhealthily for a long time, then your body is likely to be “metabolically inflexible”, meaning you can’t switch between those two sources of energy easily.

So, when you first start Keto, your body is unable to access your fat energy sources and instead keeps telling your brain that you need more sugar for energy. That then leaves you craving carbs and feeling weak.

It could be carb withdrawal

This can be thought of as resulting from withdrawal from carbohydrates (think drug addiction here). And indeed, there are studies showing that sugars (which are a form of carbohydrates) can cause drug-like addictions.

You are not fat-adapted or metabolically flexible

If you are not fat-adapted or metabolically flexible, you don't burn fat well.

You are low in electrolytes

Electrolyte deficiency causes tiredness, muscle cramps and headaches.

Frequently asked questions