Keto Flu: When To Expect The Symptoms

The keto flu is a collection of symptoms experienced by some people when they start a ketogenic diet. Symptoms include nausea, fatigue, headaches, and dizziness, and they can begin within the first 24–48 hours of starting the diet. The keto flu is caused by the body adapting to a new diet consisting of very few carbohydrates. The drastic reduction in carbohydrates can cause withdrawal-like symptoms, similar to those experienced when weaning off an addictive substance.

Keto flu symptoms

The keto flu is a collection of symptoms that some people experience when they start a ketogenic diet. These symptoms, which can feel similar to the flu, are caused by the body adapting to a new diet consisting of very few carbohydrates.

The keto flu can last anywhere from a few days to several weeks, and in some cases, symptoms may persist for up to a month.

• Stomach aches or pains: Stomach pain is a common symptom of keto flu, which can be distressing for those experiencing it.
• Nausea: Feeling nauseous is another frequent complaint of people going through keto flu.
• Dizziness: Some people may feel dizzy or lightheaded as their bodies adjust to the new diet.
• Sugar cravings: Due to the drastic reduction in carbohydrates, sugar cravings are common during keto flu.
• Cramping: Muscle cramps and soreness are also possible symptoms, especially with concurrent electrolyte imbalances.
• Irritability: The keto flu can affect your mood, and irritability is a commonly reported symptom.
• Diarrhea or constipation: Changes in bowel habits are common, with some people experiencing diarrhea and others becoming constipated.
• Trouble sleeping: Difficulty falling or staying asleep is another symptom that can contribute to fatigue.
• Fatigue: Feeling tired and exhausted is a typical symptom as your body adjusts its fuel source.
• Poor focus and concentration: Some people may experience brain fog, difficulty concentrating, or a sense of confusion.
• Headaches: The keto flu can also cause headaches, which may be related to dehydration or electrolyte imbalances.

• Stay hydrated: Drink plenty of water and other fluids to combat dehydration, a common issue during keto flu.
• Replace electrolytes: Ensure adequate intake of sodium, potassium, and magnesium by salting your food and including potassium-rich foods like leafy greens and avocados in your diet.
• Get enough rest: Make sleep a priority to combat fatigue and give your body time to recover.
• Avoid strenuous exercise: Give your body a break and avoid intense workouts during the keto flu. Opt for light activities like walking or yoga instead.
• Eat enough fat: Consume sufficient amounts of healthy fats, as they are the primary fuel source on a ketogenic diet. This will help reduce cravings and keep you feeling satisfied.

Causes of keto flu

The keto flu is a collection of symptoms that some people experience when they start a ketogenic diet. It is not an actual flu or a medical diagnosis. The symptoms arise as the body gets used to operating with fewer carbohydrates and as it enters a state of ketosis.

The ketogenic diet is very low in carbohydrates, high in fat, and moderate in protein. Carbohydrates are the body's main energy source. On the keto diet, a person reduces their carb intake to fewer than 50 grams per day, compared to the recommended 200-300 grams per day. When the body does not take in enough carbs for energy, the liver begins to produce glucose for energy, using its stores. This process is called glucogenesis. Eventually, the liver will not be able to produce enough glucose to keep up with the body's energy demands. The body will then start to break down fatty acids, which will produce ketone bodies, in a process called ketogenesis. Body tissues then use ketone bodies as fuel, and the body enters a state of ketosis.

The keto flu is caused by the body adapting to a new diet consisting of very few carbohydrates. This drastic reduction can come as a shock to the body and may cause withdrawal-like symptoms, similar to those experienced when weaning off an addictive substance like caffeine. The symptoms are the result of temporary imbalances in energy sources, insulin, and minerals in the body.

The symptoms of keto flu include nausea, fatigue, headaches, brain fog, constipation, muscle soreness, irritability, and sugar cravings. These symptoms can range from mild to severe and can last from a few days to several weeks, and sometimes even up to a month.

How to manage keto flu

Keto flu is a group of symptoms that may appear one to seven days after starting a ketogenic diet. The symptoms are usually mild and short-term, lasting between a few days and a few weeks. However, in extreme cases, they can last up to a month.

Drink More Water

Transitioning to a ketogenic diet can lead to increased urine output, which can cause dehydration and symptoms such as headaches, nausea, and constipation. Drinking plenty of water can help alleviate these symptoms and prevent dehydration. Aim for around 16 cups of water per day, but listen to your body and don't overdo it.

Get Plenty of Rest

The ketogenic diet can cause a temporary decrease in energy levels, hormonal fluctuations, and insomnia, making fatigue worse. Prioritising sleep during this time can help combat low energy levels. This means giving yourself enough time to rest, removing distractions before bedtime, and emphasising the quantity and quality of your sleep.

Eat Keto-Friendly Foods

When starting the ketogenic diet, you may experience strong cravings for carbohydrates. Instead of giving in to these cravings, try eating more keto-approved foods, such as healthy fats and proteins. Examples include unprocessed and whole foods, fatty cuts of meat, avocado, nuts, and seeds.

Consume Electrolytes

Electrolyte depletion can be a contributing factor to keto flu symptoms. Electrolytes such as sodium, potassium, and magnesium can be lost at a higher rate during ketosis. Increasing your intake of these electrolytes can help alleviate symptoms. You can get sodium from salt, potassium from non-starchy vegetables, and magnesium from nuts and seeds. Sports drinks are also an easy way to rehydrate and replenish electrolytes.

Focus on Alkaline Foods

Adopting alkaline diet principles can help reduce inflammation, restore nutrient stores, and balance your body's pH level. Focus on consuming fresh vegetables, especially green leafy vegetables, avocados, mushrooms, and green drinks made from vegetable powders. Limit caffeine, sugary drinks, and alcohol, and avoid inflammatory, processed foods.

Light Exercise

Although exercise may be the last thing on your mind when experiencing keto flu, light exercise can help relieve muscle pain and tension. Try restorative yoga, walking, or light cycling, which can also help reduce stress and improve your mood.

Remember, it is always a good idea to consult your doctor or a healthcare professional before making any significant dietary changes, such as starting the ketogenic diet. They can provide guidance and help you manage any side effects, such as keto flu.

How long does keto flu last

The keto flu is a group of symptoms that occur when people start a ketogenic diet. These symptoms are the body's response to entering ketosis, which can mimic those of the flu, hence the name "keto flu".

Symptoms of keto flu 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
• Fatigue
• Brain fog

These symptoms 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. However, depending on your genetics, you may never experience the keto flu. Some people are naturally "metabolically flexible", meaning they can shift metabolic states easily without experiencing health symptoms.

If your keto flu symptoms last longer than ten days, or if they are causing you pain or are debilitating, it is recommended that you reach out to your physician.

Who will get keto flu

The keto flu is a collection of symptoms that some people experience when they start a ketogenic diet. It is not recognised as a medical condition. The symptoms are caused by the body adapting to a new diet consisting of very few carbohydrates.

The keto flu can affect anyone who starts a ketogenic diet, but some people may find the transition period especially difficult. This is because the symptoms are tied to how the body adjusts to a new fuel source. Typically, the body uses carbohydrates to create energy in the form of glucose. When someone starts a ketogenic diet, the body has to switch to burning ketones from fat instead.

People who typically consume a lot of carbohydrates, especially refined carbs like pasta, sugary cereal, and soda, may find it harder to begin the ketogenic diet. This is because the transition to a high-fat, very low-carb diet can be a struggle for some. However, others are able to switch between fuel sources easily with little to no keto flu symptoms.

The reason some people adapt to ketogenic diets more easily than others is unknown, but genetics, electrolyte loss, dehydration, and carbohydrate withdrawal are believed to be the driving forces behind the keto flu.

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