keto flu


Keto flu is a collection of flu-like symptoms that can kick in in the early days of your keto plan. They vary from person to person - and not everyone will automatically have them.  The can include:

  • Headache
  • Brain fog and Difficulty focusing
  • Fatigue and Difficulty sleeping
  • Irritability
  • Nausea and Dizziness 
  • Sugar cravings

Remember that switching to such a low-carb diet is a major change - It’s only natural that your body may need time to adapt to this new way of eating (don’t forget sugar is addictive).

The keto way of eating is designed to lower insulin levels in your body as you go from a high to low carb diet. When your insulin levels are low, your liver will convert fat into ketones, replacing glucose as your energy source. Your body needs to adapt to this new fuel: when you drop insulin levels it excretes more sodium in your urine along with water. While this transition is responsible for some of the super-fast weight loss, the loss of water and sodium can cause these keto flu symptoms. 

Because the keto flu symptoms start while you’re making such a significant lifestyle overhaul, it can be difficult to stay on track. There are some simple fixes to support your body as it adapts, put you back in control, and feel amazing again:

Stay hydrated + add more salt
Most keto flu is caused by the sudden loss of salt and water in your body.  Upping your intake of both will  minimise the symptoms, and potentially eliminate them.  Drink at least 2.5 litres of water each day to help manage nausea and fatigue, and if you’re experiencing symptoms, add half a teaspoon of salt water.  Watch your caffeine intake - tea and coffee are diuretics so can increase water and sodium loss. About three cups of coffee a day is fine.  

Take in more fat
Carb cutting needs to be balanced with a higher fat intake. A well-balanced keto plan offers enough fat to make sure you don't feel hungry after a meal and feel energised. Research shows a higher fat intake can help reduce cravings and keep you feeling satisfied. Increasing your fat intake at the start of your keto journey can be as simple as adding some butter or avocado to your food. Once you’re fat adapted, you’ll be more in tune with how much fat you need to feel full and can cut back when your body’s adjusted to keto.  

Slow down the keto switch
If the keto flu symptoms persist, think about slowing down the transition. Allow yourself a few more healthy carbs, to an absolute limit of 50 grams a day. This will potentially slow down weight loss but will still lead to better overall health - stay away from sugar and processed foods still! Keto flu symptoms are temporary and you don’t want to undo all your great work. When you’ve adapted to low-carb eating, play around with your carb levels. You may find your body prefers eating less than 20 grams of carbs.

Go easy with exercise
Exercise is important for optimal health and keeping your body weight in check. But with so much going on, strenuous exercise should be avoided if you’re experiencing keto flu symptoms. Because fatigue, muscle cramps and stomach discomfort can be common at this stage of your keto journey, think about lighter alternatives like walking, gentle yoga or stretching. 

Prioritise sleep
With fatigue and irritability as common keto side-effects, sleep hygiene is essential. A lack of sleep causes cortisol, the stress hormone, to rise in the body and negatively impact your mood. 

Try not to give up on your keto plan! Keto flu symptoms pass and by the end of a week, your energy levels will be supercharged and you’ll be feeling better than ever!

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