In Ketosis But No Energy? How to Fix Keto Fatigue
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One important factor that affects your health and wellbeing is your energy levels.
You make diet and exercise choices based on your energy levels. In turn, these activities make a big impact on how energetic you become.
If you’re worried about why you’re fatigued on the keto diet for no reason, we’ll help you understand what’s happening.
If you find yourself in ketosis but you have no energy we can help you with why you’re feeling tired and how to fix keto fatigue.

What is Ketosis?
The keto diet changes your body’s metabolic processes by using fats instead of carbs as an energy source.
Glucose is a simple sugar that is normally your body’s primary source of energy. If there’s excess glucose, it becomes stored in the muscles and liver.
However, when your body does not eat enough carbs to meet your body’s energy needs, it finds another source of energy which is fat.
Fat gets broken down as alternative energy and produces ketones. This is your body entering a metabolic state called ketosis, the primary goal of the keto diet.
Keto, then, is a low-carb diet that forces your body to undergo ketosis.
This major change in your body can cause your lack of energy. The body still needs to adapt to the diet and must find a different way of obtaining its energy needs.
Why You’re Exhausted on the Keto Diet
Having no energy on the keto diet is what’s known as keto fatigue. This usually happens at the start of the diet.
When you’re in ketosis, your body switches its source of energy like a gasoline engine changing to an electric engine.
The adjustment period is where you may experience physical exhaustion. No matter what you do, the body and brain will go through this. This is usually called the fat-adaptation phase.
Here are the probable reasons why you have no energy on the keto diet.
Keto Flu
Weak physical performance is one symptom of the dreaded keto flu. This condition is remarkably similar to the flu, although the cause is different.
Many who are first starting the keto diet suffer from some keto flu symptoms, so you don’t have to worry. In a few weeks, you’ll be back up and ready to be active again.
The keto flu usually starts on the second or third day of the diet as your carb stores are depleted.
Symptoms include:
- fatigue
- irritability
- nausea
- dizziness
- brain fog
- constipation
- leg cramps
- dry mouth
- excessive sweating.
The keto flu only lasts for a week or two. Some don’t even experience it at all.
The flu also comes with frequent sweating and urination. As you lose a lot of bodily fluid, you become more dehydrated and weaker.
Not Enough Exercise
Just because keto will make you lose weight doesn’t mean you shouldn’t move your body anymore.
You might be wondering how you’re supposed to exercise on keto when you don’t have the energy. Remember that a sedentary lifestyle could be what’s making you feel tired.
Low-intensity exercises like walking and yoga can help you feel the right kind of tired.
Low Calorie Intake
Restricting calories without counting or being intentional can burn fat and lose weight, but under-eating can reduce your body’s production of thyroid hormone and other hormones.
On the keto diet we often don’t pay attention to our calorie intake, focusing instead on our carb intake. As a result, it is possible that you could end up eating too little.
Most of your calories should be coming from fat. If you don’t have enough fats on keto, you’re going to feel more fatigued.
Don’t worry though. Fat won’t make you fat.
Dirty Keto
You might be tracking your macros on keto, but you might be eating a lot of unhealthy food to insure your high-fat diet intake.
Eating fatty food and other processed food won’t do you any good. These things contain a lot of artificial flavors, colors, and other additives which worsen your fatigue.
The wrong kind of fat sources can result in mineral deficiencies and omega-3 and omega-6 imbalances.
This could be a factor in your lack of energy.
How to Fix Keto Fatigue
Aside from simply waiting it out, there are some ways to fix or reduce keto fatigue.
Eat More Calories
As mentioned, eating below the normal caloric intake reduces your body’s production of energy hormones, so try eating a few more calories.
Just consider your macro ratio on keto, making sure that you’re still eating high-fat, moderate-protein, and low-carb. Learn how to compute your macros on keto.
Ideally, 60%-80% of our calories must come from fats, 20%-35% from protein, and 5%-10% from net carbs.
Always go for keto-friendly whole foods for your source of energy. You’ll be amazed at how much better you’ll feel with healthier foods.
In general, your calories should come from fat. Choose healthy fats on the ketogenic diet to ensure you get more energy.
Eat at the Right Time
Many are fixated on what to eat that they forget when to eat. Your meal schedule affects your energy levels, especially if you are on the ketogenic diet.
This is even more critical if you aren’t fat-adapted yet. Don’t do intermittent fasting on your first week of the diet.
Try to eat three meals a day, with a few low-carb snacks in between.
Try Ketone Supplements
Ketone supplements are designed to help you get into the state of ketosis quicker. They also support a healthy lifestyle by providing nutrients you may be lacking on the low-carb diet.
Ketone supplements can come in the form of MCT oil, BHB salts, and more.
Supplements can help lower the negative side effects of getting your body fat adapted.
Check out our recommendations for supplements for the keto diet.

FAQ Ketosis and the Keto Diet
Do Calories Count on Keto?
Yes.
Calories count on the keto diet. However, they are not everything.
The diet focuses more on the components of the calories you’re consuming rather than the number of calories you’re eating and drinking.
This means that the question isn’t how much, but what kind of food you should eat.
We’ve mentioned that keto is a high-fat, moderate-protein, and low-carb diet.
Check out the importance of calories on the ketogenic diet!
Can Ketone Supplements Help with my Fatigue?
Yes.
Ketone supplements can help support your health on the keto diet by enhancing your ketosis and providing the nutrients you need on the keto diet.
Compared to other weight loss supplements, ketone supplements only help support your diet and maintain your weight.
You cannot use them on their own without being on the diet and still expect to see results.
We have a guide that shows you what ketone supplements do!
What Type of Exercise Should I Do on Keto?
Ketosis may leave you feeling tired and fatigued all the time, which can be another excuse to stop working out.
But it’s recommended to do light exercises on the diet. You can do yoga, light cardio, and other types of exercises as long as it is not extensive or intense.
Avoid high-intensity workouts like HIIT, circuit training, and any other intense workouts.
Once you get your energy back, you can finally exercise the right way on keto!
Can I Eat Too Much Fat on Keto?
Fat is an essential part of the keto diet. It makes up most of your calories for daily fuel instead of carbs or glucose.
We know that keto is a high-fat diet. But how high is too high?
The answer varies among every keto dieter, but you can eat too much fat on the keto diet.
Aside from the possibility of getting kicked out of ketosis, there is also a risk of heart disease and more. This is why it’s important to choose high-quality fats.
Learn what else happens when you eat too much fat on the keto diet!
If All Else Fails…Wait it Out!
If you’ve tried everything to get back your energy on the keto diet and it still didn’t work, just take a beat and wait.
Remember, no matter what you do, your body will have to adjust to the ketogenic diet. This period can last for a week or two.
So, just give it some time to make physical exercise and mindful eating more effective.
Ease in to this new way of eating and make sure you are getting enough good quality fats from whole food sources.
You also might want to try ketone supplements. Check out the best BHB salt to try on the keto diet.