Menu Close

The “Keto Flu”

The Keto Flu

When considering the keto diet, one of the earliest difficulties experienced is the “keto flu”. This non-medically recognized phenomenon is not an actual illness, but rather a collection of symptoms you may experience as a result of transitioning your diet. For this reason, the keto flu is often interchangeable with “carb withdrawal”. Though it might be tempting to throw in the towel at the onset of these unforeseen symptoms, knowing how to tackle the momentary trial (and knowing that it is momentary) is super helpful to coming out victorious. Below, we’ve listed some of the common symptoms, how long the keto flu may last, and how to alleviate the symptoms to get you back on your feet!


  • Headache
  • Brain fog
  • Irritability
  • Nausea
  • dizziness
  • Fatigue
  • Difficulty sleeping
  • Constipation
  • Cramps and sore muscles
  • Stomach pain
  • Vomiting
  • diarrhea
  • Sugar cravings


The keto flu typically begins 24-48 hours after beginning a ketogenic diet. It typically would last a couple days to one or two weeks, and up to one month at longest. Since everyone’s symptoms vary across the board though, the severity of symptoms can differ, as can the length of time, or even whether someone on the keto diet experiences the above at all.


  • Hydration: The keto diet can be initially harsh on your fluid balance, making you more dehydrated than normal. Good hydration can alleviate symptoms, such as muscle cramps and fatigue. One daily goal I like to shoot for is to drink 1 ounce of water per 2 pounds of body weight.
  • Salt: A teaspoon of salt per day can help balance the way your body excretes sodium when experiencing the keto flu. When transitioning away from carbohydrates, levels of insulin decrease, stimulating the kidneys to release excess sodium. Furthermore, the change in food types may result in a lower level of sodium than your previous diet.
  • Sleep: When you are experiencing difficulties with sleeping, stress hormone (cortisol) levels can rise, affecting mood. Setting a regular bedtime to sleep and wake up can help improve sleep quality. As usual, you can improve the quality of sleep by also dimming lights and reducing caffeine intake in the hours before bed.
  • Electrolytes: Adding pumpkin seeds, almonds, spinach, and avocado to your diet can alleviate insufficient levels of electrolytes.
  • Low intensity exercise: strenuous exercise should be minimized when experiencing these symptoms as your body adjust to the new diet. Examples of low intensity exercise include walking, yoga, or light weightlifting.

Overall, the keto flu is a season of the body adjusting to a new energy source, and whether it’s genetics, how close your previous diet was to being keto-friendly, or any other possible cause, people vary across the board with how many symptoms they experience, as well as to what degree. Knowing why your body is reacting this way is power to take the measures to alleviate the symptoms, which are often linked to insufficient hydration and electrolyte levels.