Over the first few days (up to two weeks) of eating low-carb, you may run into some frustration. Where is all of this energy I’m supposed to have? Why do I want to mow through that bag of chips right now? Am I coming down with a cold? For some people, the transition from burning glucose to burning fat comes with unwanted symptoms that range from slightly uncomfortable to miserable. This transition period is known as keto flu, or low-carb flu. It’s real, and it can be pretty terrible.
But, it’s temporary.
What is Low-Carb Flu?
Low-carb flu, or keto flu, is a set of symptoms that you may feel over the first few days of limiting carbohydrates. Low-carb flu isn’t a flu or infection at all, and it’s not a medical term. It got its name because some of the symptoms of carb restriction can feel like you’re sick with the flu.
Low-carb flu has dissuaded millions of people from pursuing and sticking to a healthy diet. You can laugh now that you’re fat-adapted and humming along on stored body fat, but you’ve forgotten just how terrible the transition from sugar-burning to fat-burning can be.
Symptoms of Keto Flu, or Low-Carb Flu
A little planning and motivation will help you start a low-carb, keto, or Primal lifestyle, and under normal circumstances, keeping your carbs on the low side is easy. But let’s not create the illusion that it is easy all the time. From time to time, you may get stressed and eat mindlessly. Or, your aunt drops off her blue-ribbon cake that you’ve loved since you were in preschool, and you give in, just this once. Or, you had a jam-packed day and all you can muster to make for dinner is that package of gluten-free noodles in the back of your pantry. The next thing you know, you’ve eaten enough carbs for a week, and you wonder how you’ll get back into ketosis after a carb binge.
The short answer is, yes you will recover from a carb binge. Yes, you will get back into ketosis. As far as how long it will take to get back into ketosis – that depends on numerous factors, that we’ll dive into here. The important thing to remember is, you did not obliterate your goals with one misstep. Especially after you’ve spent some amount of time in ketosis, your body will allow for fluctuations in carb consumption here and there. That’s called metabolic flexibility, which we’ll go into shortly.
Conquering carbs offers a whole constellation of rewards, not the least of which is a steady, brisk energy unlike most people have known before (well, maybe since the whirling age of 10 or so…). People tell me constantly that they can finally make it through the day without being down for the count every midafternoon. They enjoy enough vigor and vitality to weather a whole day’s worth of activity. The busyness of life becomes easier to handle: the energy demands of daily work or business travel, the mayhem and constant commotion of kids, a weekend’s worth of chores and errands, etc. A skipped meal doesn’t suddenly change the agenda to including procuring a bagel or other false pick-me-up. Nonetheless, for some folks, there’s a common, temporary but still bothersome bump in the road on the way to that Primal prize. Though it varies, it often means a couple weeks of mental fuzziness, fog and fatigue. Although your body might be off to the races, your brain can lag behind like a little brother in a stuffed snowsuit. It’s a game of “hey, wait up!” while the body’s mechanisms and metabolism align themselves. They call it “low carb flu,” and rest assured it’s just as temporary.
I just want to know if anyone who has been Primal for some time had any trouble with cognition in the first few weeks. I can hardly think straight, especially after eating, and I am also low on energy. Will this pass??? Besides that, my body feels great!”