Keto Flu: When To Expect This Unpleasant Side Effect

The keto flu is a collection of symptoms that some people experience when they start a ketogenic diet. The symptoms, which can feel similar to the flu, are caused by the body adapting to a new diet consisting of very few carbohydrates. Symptoms of keto flu can include nausea, constipation, headaches, fatigue, and sugar cravings. They can start as early as the first day of the diet and can last for a few days or up to several weeks.

Keto flu symptoms

The keto flu, also known as the "carb flu", is a group of symptoms that occur in response to carb withdrawal. This happens when your body enters ketosis, which is a metabolic process where your body, instead of burning carbohydrates (glucose) for energy, burns fatty acids for energy.

Symptoms of the keto flu can begin within the first day or two of starting the keto diet, and they can range from mild to severe. 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 of the most common symptoms of the 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
• Brain fog
• Headaches
• Fatigue

These symptoms can be uncomfortable, but there are ways to manage and reduce them. Here are some tips to help you deal with the keto flu:

• Transition gradually: Instead of drastically cutting carbs, slowly reduce your carb intake while increasing the amount of fat and protein in your diet. This can help you ease into the keto diet and make the transition smoother.
• Drink plenty of water: The keto diet can deplete your water stores, putting you at risk for dehydration and electrolyte imbalances. Staying hydrated helps replace lost fluids and minimizes symptoms like fatigue.
• Get enough electrolytes: When your body dumps water during ketosis, it often dumps electrolytes too. Adding more salt to your food or drinking sports drinks that are high in electrolytes can help your body adjust to ketosis more smoothly.
• Get plenty of rest: If you're having trouble sleeping, try taking an Epsom salt bath to relax your muscles and improve electrolyte absorption. You can also drink keto-friendly herbal tea with calming herbs to promote a deeper sleep.
• Adjust your workout routine: Avoid strenuous exercise if you're experiencing keto flu symptoms. Focus on lighter activities such as walking or yoga instead.
• Moderate caffeine intake: Caffeine can negatively impact sleep, so cut back on caffeine if you're having trouble sleeping.

How to reduce keto flu symptoms

The keto flu is a group of symptoms that may appear within the first two to seven days of starting a ketogenic diet. Symptoms can range from mild to severe and can last from a few days to several weeks. The good news is that you can take steps to reduce them. Here are some ways to reduce keto flu symptoms:

• Transition gradually: Instead of drastically cutting carbs, slowly reduce your carb intake while increasing the amount of fat and protein in your diet. This can help you ease into the keto diet and make the transition smoother.
• Stay hydrated: Drinking enough water is crucial for reducing keto flu symptoms. The keto diet can deplete your water stores, putting you at risk for dehydration and electrolyte imbalances. Staying hydrated helps replace lost fluids and minimizes symptoms like fatigue.
• Adjust your workout routine: Avoid strenuous exercise if you're experiencing keto flu symptoms. Focus on lighter activities such as walking or yoga instead.
• Moderate caffeine intake: Caffeine can negatively impact sleep, and it's common for people with keto flu to have trouble sleeping. Reducing your caffeine intake can help lower this risk.
• Supplement with electrolytes: An extremely low-carb keto diet means cutting out foods rich in electrolytes, such as starchy fruits and vegetables. Adding electrolytes like salts, potassium, and magnesium to your diet can help prevent cramps and nausea.
• Eat plenty of vegetables: Include a variety of non-starchy vegetables in your diet, such as spinach, leafy greens, broccoli, cauliflower, and Brussels sprouts. These foods are rich in essential electrolytes and can help minimize digestive issues associated with the keto flu.
• Get plenty of rest: If you're having trouble sleeping, try taking an Epsom salt bath to soothe and relax your muscles and improve electrolyte absorption. You can also drink herbal tea with calming herbs to promote a deeper sleep.

Remember, it's always a good idea to consult your doctor before starting any new diet, especially if you have concerns or experience persistent symptoms.

What causes keto flu

The keto flu is a group of symptoms that may appear within the first two to seven days of starting a ketogenic diet. The symptoms are your body's response to entering ketosis, which can often mimic those of the flu.

The ketogenic diet involves reducing your carbohydrate intake to a minimum, forcing your body to burn fat for fuel. Normally, your body only enters ketosis if you're starving or fasting. The sudden switch from burning carbohydrates to burning fat can be confusing for your body, and it can take some time to adjust to this new way of eating.

The most common causes of keto flu include sodium deficiency, dehydration or overhydration, carb withdrawal, and reduced brain fuel.

Sodium Deficiency

When you minimise carbs, you also minimise the hormone insulin, which tells your kidneys to retain sodium. With less insulin, your body excretes too much sodium through urine, leading to sodium deficiency. Symptoms of sodium deficiency include headaches, weakness, low energy, fatigue, muscle cramps, brain fog, insomnia, salt cravings, and irritability.

Dehydration or Overhydration

The keto diet can quickly deplete your water stores, putting you at risk of dehydration and electrolyte imbalances. Additionally, ketones have a diuretic effect, so you may urinate more frequently when on the keto diet. Symptoms of dehydration include headaches, weakness, low energy, fatigue, muscle cramps, constipation, dark urine, dry skin, decreased urinary volume, and rapid heartbeat. Overhydration can also dilute blood sodium levels and exacerbate low sodium symptoms. Symptoms of overhydration include headaches, confusion, muscle cramps, low energy, and irritability.

Carb Withdrawal

Carbs and sugar activate reward pathways in your brain, so eliminating them can cause carb cravings and other "withdrawal" symptoms. While sugar is not an addictive drug, it can trigger similar brain systems as addictive drugs, such as causing a release of dopamine. Symptoms of carb withdrawal include hunger, carb cravings, mood fluctuations, low energy, headaches, and fatigue.

Reduced Brain Fuel

When you reduce your carb intake, your brain has to use fat as fuel instead. Some people can transition to this fat-burning state quickly, while others may take a few days or weeks to adjust. During the transition, cognition-related keto flu symptoms can arise, including headaches, brain fog, low energy, and fatigue.

How long does keto flu last

The keto flu is a group of symptoms that may appear within the first two days of starting a ketogenic diet, as your body enters ketosis. For the average person, the keto flu can last about 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.

The keto flu is essentially your body experiencing symptoms of withdrawal from carbs. Your body typically burns carbohydrates (glucose) for energy, so switching to a fat-burning process can be confusing for your body. When you drastically reduce your carb intake, your body is depleted of stored glucose and turns to burning fatty acids for energy. This metabolic process is called ketosis.

The symptoms of keto flu can range from mild to severe and may include:

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

While the keto flu is usually temporary, it can be unpleasant. However, there are some steps you can take to reduce the symptoms:

• Transition gradually: Instead of drastically cutting carbs, slowly reduce your carb intake while increasing your consumption of fat and protein. This can help you ease into the diet and make the transition smoother.
• Stay hydrated: The keto diet can deplete your water stores, putting you at risk for dehydration and electrolyte imbalances. Drinking plenty of water can help reduce symptoms like headaches and fatigue.
• Get your electrolytes: An extremely low-carb keto diet means cutting out some of the richest natural sources of electrolytes, such as starchy fruits and vegetables. Adding more salt to your food or drinking sports drinks that are high in electrolytes can help your body adjust to ketosis more smoothly.
• Get plenty of rest: If you're having trouble sleeping, try taking an Epsom salt bath to soothe and relax your muscles, as well as improve electrolyte absorption. You can also drink keto-friendly herbal tea with herbs that calm your nervous system, such as chamomile.
• Try light exercise: Light exercise, such as restorative yoga, can help relieve muscle pain and tension, boost your mood, and improve your motivation.

Who is likely to get keto flu

The keto flu is a set of symptoms that some people experience when starting a ketogenic diet. It is important to note that keto flu is not a recognised medical condition. It is the body's response to entering ketosis, which can often mimic flu-like symptoms, hence the name.

The keto flu is likely to hit those who drastically and suddenly remove carbs from their diet. The ketogenic diet is a low-carb, high-fat, and low-to-moderate protein diet. This usually works out to be 70% to 80% fat, 10% to 20% protein, and 5% to 10% carbohydrates. The keto flu is caused by the body's withdrawal from carbs, as the body burns carbohydrates (glucose) for energy by default. Therefore, those who typically consume a lot of carbs, especially refined carbs like pasta, sugary cereals, and soda, are more likely to experience the keto flu.

The symptoms of keto flu usually appear within the first two days of starting the diet, but they can also take up to a week to appear. The symptoms can range from mild to severe and can last from a few days to several weeks, and in extreme cases, up to a month. Some of the most common symptoms include stomach aches, nausea, dizziness, sugar cravings, cramping, muscle soreness, irritability, diarrhoea, constipation, trouble sleeping, poor focus and concentration, and brain fog.

It is important to note that not everyone will experience the keto flu when starting a ketogenic diet. Some people are naturally "metabolically flexible", meaning they can shift metabolic states easily without experiencing any negative health symptoms. Additionally, the keto diet may not be suitable for everyone, including pregnant or breastfeeding people, children, and teens, unless under medical supervision.

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