Switching your fuel source from carbs to fats on the ketogenic diet can be accompanied by a transition phase. It is what we call the “keto flu”.
Even though the diet has been proved to be the most effective for weight-loss, the symptoms during the keto flu are unpleasant.
However, it can happen that you don’t get any symptoms or experience any critical issue.
The most important thing to know is that it’s all normal for your body to feel this in order to adapt to the ketogenic diet.
You just have to be aware of the risks that might happen and deal with them.
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What Is The Keto Flu?
The keto flu is simply a set of symptoms that appear during the first days or weeks of the keto diet.
They are very similar to the flu symptoms. That’s why we call it “keto flu”.
In fact, carbs are burned first by our bodies for energy. After that, protein and fats are consumed.
The body is used to having sugar as the main source of fuel. So, it’s easier to burn it first.
However, when you drastically cut carbs on the keto diet, we force it to burn ketones instead of glucose.
Ketones are produced in the liver after burning fats. They are very potent but usually stored as a second source of energy.
If you are starving or cutting on carbs your body uses ketones and thus, gets into a metabolic state called ketosis.
Unfortunately, the change to this state is not immediate. You need time to adapt to the new ketogenic lifestyle.
Think about it as applying a new habit. It takes time to learn it even though there is a great reward.
Keto Flu Symptoms
The symptoms are very similar to the flu and can be gone in a few days or even less.
However, once you get past this period, the reward is great. Most people report increased energy, mental clarity, and faster weight-loss.
On the other hand, it can be critical for some people. Especially if you have a medical issue.
In this case, always consult your doctor even before starting the keto diet.
Here are some of the common keto flu symptoms that might occur because of the lack of energy or the lack of nutrients on the ketogenic diet:
- Low energy
- Lack of motivation
- Brain fog
- Sugar Craving
How To Deal With The Keto Flu?
Flu-like symptoms are most likely to disappear during the first few days on the keto diet.
Most people said that it took them 3-4 days to get past the keto-flu completely. Some don’t experience it at all.
It is very rare for the flu symptoms to stay longer than a week.
This period is usually when most dieters throw the towel because it’s the hardest.
The symptoms will eventually fade away but we don’t want them to kill your motivation.
There are tons of things that you can do to make the process easier, faster, or even get rid of them once and for all.
Here are some ways to deal with the keto flu:
Eat More Fats
As long as there is a very low amount of carbs you have to make sure that you are getting the adequate amount of fats to fill that void.
On the ketogenic diet, you will have to eat more fats than you normally would. So, basically, if you lack the energy you lack fats.
Consuming enough fats will help you ease the pain of the keto flu.
Some symptoms like brain fog and lack of motivation will be easier to handle with enough fats.
Also, this will help you crave less sugar (*).
However, if you want to lose weight with the keto diet you have to create a caloric deficit.
This means you have to eat less calories than what your body really needs.
Fats are the most caloric dense nutrients. They have a lot of calories which can add up easily in your daily intake.
It’s great to eat more fats but always calculate your macros if you want to stay on point.
Less Intense Physical Activities
If you are an athlete or a weight lifter you have to take it easy during the keto flu.
This doesn’t mean that exercising is not good on keto diet.
Not at all. It’s always better to exercise while you are on a keto diet if you want to stay healthy.
However, during the keto flu, some symptoms like muscle cramps and fatigue can get in the way of your athletic performance.
Not only you will feel tired quickly but you may also negatively affect your body.
That’s why you have to give the body a rest during the keto flu.
Heavy weight lifting, intense biking, or running should be avoided, while there is no harm in light activities like walking or lightweight training.
They can also help dealing with the keto flu symptoms.
You have to drink enough water no matter what your diet is. On keto, you just have to drink more.
When you restrict carbs you will notice a big weight-loss during the first week. This is mostly water weight.
In fact, water is stored in your body with the help of glycogen which comes essentially from carbs.
On the keto diet, you will lose glycogen from your body and thus your water mass. This can cause dehydration (*).
This can be the reason behind many symptoms like fatigue and brain fog.
In order to avoid dehydration, you have to drink more water or fluid to replace the one lost in the urine.
2.5 Liters is the minimum recommended during the keto flu. But when your body adapts, you can drink less while keeping a minimum of 2 Liters per day.
Gradually Cut On Carbs
If you are drinking more water, getting enough rest, and eating more fats but you still suffer from the keto flu, eat slightly more carbs.
Some people have a hard time restricting carbs drastically. It’s better to do the transition slowly in this case.
You can start by cutting sugary foods at first such as bagels, bread, and candies. Then you can slowly decrease carbs until you get to 20-50 grams per day.
Once you get past the keto flu, you can make it to less than 20 grams of net carbs and see how your body will respond.
This makes the transition smoother and easier, but it slows down your progress.
It might take longer to get into ketosis or to lose weight. But if you find it hard to deal with the keto flu it’s better to take it slowly.
Consume More Fibers
The main goal of the ketogenic diet is getting into ketosis. That’s why we restrict carbs.
However, not all carbs are created equal.
On the ketogenic diet, we have to limit net carbs (or sugars). This spike your blood sugar levels which can kick you out of ketosis.
On the other hand, the diet doesn’t restrict fibers because they are very important for the body. Plus, they are the least type of carbs that affect blood sugar levels.
Also, most of the digestive issues are usually related to the lack of fibers (*).
Fortunately, there are a lot of low-carb vegetables that provide an adequate amount of fibers.
Some examples: Avocado, Cauliflower, Mushrooms, Red cabbage…
Can Supplements Help On Keto Flu?
If you are still dealing with the keto flu, trying everything but nothing works you will feel miserable.
Most probably you will give up at this point because of the lack of motivation.
In this case, you can use some supplements for the help.
However, the typical question always arises. Are supplements required on the keto diet?
The short answer is NO. As the name indicates, supplements are just for supplementation. It’s usually better and possible to get all you need from whole foods.
Fortunately, the list is very large but you have to be careful with what you choose.
Some supplements will increase ketones to help you get faster into ketosis. Others can prevent muscle breakdown and reduce dizziness by providing essential nutrients.
The choice is yours. It really depends on your needs.
Here are some useful supplements to help you ease the keto flu symptoms:
- MCT Oil
- Exogenous Ketones
- Digestive Enzymes
- Fish Oil
Keto Flu Risks
The good thing about the keto flu is that it will eventually fade away. However, it can cause some problems in some cases.
Most of these problems are related to the balance of your diet. So, always try to include all the necessary nutrients.
Here are some risks that might occur with the keto flu:
Lack Of Nutrients
It’s very common for the low-carb diets to provide fewer nutrients than needed since they restrict several foods like whole grains and legumes.
Some studies have shown that the types of food on the Atkins diet, which is very similar to the keto diet, provide only 12 vitamins from the 27 needed.
Well, to be fair, most people don’t get 27 vitamins with the appropriate amounts everyday which can lead to nutrients deficiency over time.
It is suggested to eat more low-carb vegetables on a keto diet as they are rich in nutrients and minerals.
Also, you can use supplements if you are not getting enough nutrients from foods.
Increase The Risk Of Chronic Diseases
If you suffer from a chronic disease it is better that you stay away from the keto diet because it may be harmful to your current situation.
On the keto flu, you might find yourself wanting to restrict most foods to get into ketosis as fast as possible.
Even though that might get you somewhere, pay attention to your protein daily intake.
In fact, it shouldn’t be restricted or depending only on animal sources as this can lead to some very serious issues.
A study compared a diet where protein sources are mostly animal and another one where they are based on veggies documented that the first one may result in poor health outcomes.
On the other hand, protein sources coming from vegetables can lead to several health benefits (*).
Is The Ketogenic Diet For You?
Regarding all the benefits and the risks that might result from the keto diet, you should always ask this question, even before you start.
The good news is that for most people it won’t be a problem. You can start your diet immediately and be patient to get through the keto flu.
Some of you won’t feel anything. Their bodies will smoothly adapt to the keto diet.
The point is, you already know your body and what is going on with it. If you suffer from a diagnosed disease then the keto flu can worsen it and you should consult your doctor first.
Also, focus more on vegetables and nutrients to get a balanced diet. And, don’t give up. It’s just a matter of time until the keto diet becomes part of your lifestyle.
Wondering what to eat on a keto diet?
We provide you a 7-day keto plan with our top picks dishes. We made sure that you will get low-carbs and high-fat meals with the most tasty flavors. And, of course, we want it to be for everyone, that is why it is a Plan on Budget.