Everything You Need To Know About The Keto Flu

Everything You Need To Know About The Keto Flu

 

Author: Casey Thaler

 


The standard American diet is quite high in carbohydrates. French fries, pizza, popcorn, chips, candy, soda - these are (unfortunately) the cornerstones of many American diets. A ketogenic diet turns this approach on its head, as in it completely reverses the macronutrient ratio. High in fat, extremely low in carbohydrates - and great for weight loss. The keto diet is rapidly gaining in popularity, and monthly Google searches have expanded to over one million per month to prove it.

But switching to a keto diet isn’t always easy; the adaptation period can be notoriously bad, especially if you quickly switch from eating tons of carbs to eating none. Or if you don’t carefully consider what nutrients and other elements are needed to support a healthy keto diet. While the high fat nature of the keto diet gets a lot of press, what’s less focused on yet equally as important is the need for electrolytes, and micronutrient deficiencies that can develop (if you fail to follow a carefully crafted plan).

Because starches, fruits, sugar, and other foods are limited in consumption, we must consider what else these foods provide besides carbohydrates. Vitamins, minerals, micronutrients, etc. Since our body is switching from burning glucose for fuel, to using fat, it’s in need of even more nutrients during the transition process. For example, sodium excretion goes up when we switch to a keto approach, which means you need to intake more sodium than usual to support the change.

This adaptation period is commonly referred to as the ‘keto flu.’ Much like the regular flu, there is a laundry list of symptoms that occur when switching from carbs to fat as our main source of fuel. Sleeplessness, brain fog, fatigue, muscle cramps, nausea, irritability, and constipation (to name a few) are all common side effects and symptoms of the keto flu. While there is no established, scientific diegnostic behind the keto flu, everyone who goes keto can attest to how very real it is.

The first thing we need to mention - you’ll want to do all you can to minimize the symptoms, which almost goes without saying. Much like the regular flu, the keto flu is incredibly uncomfortable and will leave you feeling pretty crumby. The best thing to start with? Drink plenty of water. The standard recommendation is 8 glasses (of 8 ounces) of water per day, but shockingly, many of us don’t even hit this relatively low number. While going keto can require more water in general, clearly most of us don’t drink enough of it to start with. 

A better number to shoot for would be 16 glasses, or simply one gallon of water per day. Exercise, a keto diet, and numerous other factors can also increase the need for water consumption. For example, I drink slightly under a gallon and a half of water, per day, I exercise regularly, and I consume a keto diet - so ‘extra’ water helps me maintain optimal health. And this extra consumption of water is even more crucially important during the keto adaptation phase.

That’s because, while less severe in nature, carbohydrate and sugar withdrawal is not all that different than drug withdrawal. Essentially, you are reprogramming and retraining your cells to function in a different way, and without the fuel they have grown accustomed to consuming regularly. Sugar is the most direct element to this drug analogy - as it rewards the brain in the same way as many addictive substances.

As our blood sugar drops in response to fewer carbohydrates, we fall into hypoglycemia (low blood sugar). Then our hormones, water levels, and electrolytes all need to adjust to a much lower carb intake. This sounds easy, but it often takes days or weeks. As we intake more dietary fat, our body takes this fat and breaks it down into ketones, which our body and brain uses for energy. However, if we eat too much protein our body can actually be kicked out ketosis. This is because our body actually takes this excess protein and breaks it down via a process called gluconeogenesis.

This process is different from beta-oxidation, which is the process where dietary fat is turned into energy. Essentially, the keto flu is largely caused by the period where the body doesn’t really know what’s going on, when it’s ultimately just suffering from low blood sugar. Since it automatically thinks more energy is coming via carbs, it doesn’t know what to do with all the extra fat, and as a result you can feel sluggish and cranky. The expected energy - carbs - aren’t actually coming. Eventually your body adapts, but not before the flu period.

Another interesting mechanism is the dopamine system which is altered via regular carbohydrate and sugar consumption. Essentially, over time, our brain becomes more accustomed to these substances and as a result wants more and more. By taking away carbs and sugar (especially when done abruptly) - we notice a change in dopamine, and tend to feel cranky as a result.

Calcium, potassium, sodium, magnesium, and chloride. What do all of these have in common? They are all electrolytes and they’re crucially for our body to function properly. When switching to a keto diet - you guessed it - these may be in short supply. Less insulin is released when we consume fewer carbs, which causes the kidneys to get confused; they store less water, which explains our need for increased water consumption. This is also where more sodium intake is required - since your body naturally expects more, you need to increase sodium intake during the process of shifting into ketosis.

So in summary - what’s the best way to combat and avoid the dreaded effects of the keto flu? Drink plenty of water, eat plenty of fat, rest, avoid strenuous exercise at first, and supplement accordingly. Supplementing with additional ketones, electrolytes, vitamins, and minerals will help your body adapt much more easily, and much faster. And remember - the keto flu isn’t forever. Stick it out for a few days or weeks that it’s there. Soon you’ll reap the rewards of being a certified, ketogenic, fat burner!

 

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