Calorie restriction diets are one-trick ponies – they work by creating a calorie deficit that forces your body to burn stored fat for fuel. This type of diet limits the amount of food you eat. It’s simple mathematics – eat fewer calories to burn more fat.
Diets like this work in one of several ways including:
- Smaller meal size
- Less frequent meals
- Less sugar or fat
- Replacing high-calorie meals with low-calorie shakes, bars, or soups
- Eliminating certain foods or food groups
- A combination of the above
The keto diet is different. It changes the way your body makes and uses energy to maximize fat burning. There may still be a calorie deficit, but this secondary to altering how your body functions. In fact, a lot of people are surprised that, initially at least, they don’t even have to count calories to lose weight on the keto diet.
These changes take time, and the process of making them is often called keto induction. Keto induction is unavoidable and not always pleasant. However, once you have completed the induction phase of your keto diet, you’ll be all set for fast fat burning and easy weight loss.
In this guide, we reveal the causes and effects of descending into ketosis so that you know what to expect and can take steps to make entering ketosis as easy as possible.
Keto Induction Phase
What is keto induction?
Your body likes to use carbohydrates for energy. Carbs are broken down into glucose, and that glucose provides energy for your brain and for your muscles. Your body also uses fat for fuel, but it tends to prefer to use carbs and store fat for later use.
This is an evolutionary throwback to our hunter/gatherer days when food was often in short supply. Stored body fat could be the difference between life and death when there was no food to eat.
The leaner you were, the more quickly you would have experienced starvation. Fat is like money – you can save it for the future. Your body is especially frugal with fat and really doesn’t like to spend it unless it absolutely has too.
Fast forward to the 21st century, and our bodies still like to store fat, even though food is abundant. High carb diets are particularly problematic as all those carbs mean your body seldom needs to burn fat for fuel. Even low calorie but high carb weight loss diets can be ineffective.
Your body doesn’t know you are purposely eating less food. It still thinks you are in the throes of famine. Subsequently, it does all that it can to retain your body fat. Stupid body!
With the very low carb ketogenic or keto diet, you purposely reduce your carb intake to 50 grams or less per day. This forces your body to use fat for fuel. However, your brain and your muscles don’t run very well on fat. Instead, it converts fat into ketones – a substance your brain and muscles can use for energy.
This process is not very efficient, and it takes a lot of fat to make a relatively small number of ketones. This increases your calorie expenditure, leading to faster fat loss. This state is called ketosis. It’s a perfectly natural human condition and is another built-in survival mechanism for dealing with famine.
However, before your body can make the shift to using ketones for energy, it has to use all of the carbs stored in your body. Your body stores carbohydrate, in the form of glycogen, in your muscles and liver.
During the induction phase of the ketogenic diet, your body uses your onboard glycogen stores, but they aren’t replaced. This can lead to a range of symptoms that are collectively called the keto flu. The keto flu can last several days to a couple of weeks depending on how much glycogen you have in your body and how quickly it is depleted.
As your glycogen levels are depleted, your reliance on ketones increases. When your body finally makes the shift to exclusively using ketones for energy, your keto flu symptoms will vanish, and you’ll feel great. As well as feeling better, you’ll also start burning fat at an accelerated rate. Until that point, you may not feel so good.
Depleting your glycogen stores takes time, and it’s an unavoidable process. The good news is there are there several things you can do to make entering ketosis quicker and easier.
Timeline and what to expect
The duration of the keto induction phase varies from person to person. For some, it’s all over and done in five days or so. Other people are in the throes of keto induction for two weeks. Once you quit carbs, you’ll probably start noticing some signs and symptoms during the first 2-3 days, and then things may worsen after that until you make the switch to full ketosis.
For most people, days 4-7 tend to be the worst, but then things start to get easier thereafter. Other people sail through keto induction and end up wondering what the fuss was all about!
Why do some people enter ketosis faster and more efficiently than others? Good question! It all comes down to the size of your glycogen stores and how quickly you can deplete them.
The size of your glycogen stores is dependent on several things:
1) The more carbs you eat, the more glycogen you are likely to have. If like most Americans, you currently get most of your calories from carbs, you probably have pretty big glycogen stores.
2) Bigger muscles tend to have bigger glycogen stores. Glycogen is a large, bulky molecule and the more space you have, the more glycogen you’ll be able to store. Men typically have bigger muscles than women, and subsequently, have larger glycogen stores. This means men may experience a longer keto induction phase than women.
3) Athletes are better at storing glycogen than sedentary people. One of the reasons that athletes can keep exercising for long periods is that their bodies are particularly good at storing lots of glycogen. This is a by-product of regular exercise. If you exercise frequently, you have a greater ability to store glycogen.
Speed of glycogen depletion depends on several additional factors:
1) Glycogen is your muscle’s preferred source of energy during physical activity. The more active you are, the faster you will deplete your glycogen stores. In contrast, if you are mostly sedentary, your glycogen stores will last longer.
2) How strictly you adhere to your diet. The lower your carb intake is, the faster you will deplete your glycogen stores. If during the induction phase of your keto diet, you keep cheating and eating carbs, or you don’t reduce your carb intake to 50 grams or less per day, depletion will take longer.
All of this information means that keto induction time varies from person to person. Some factors are unmodifiable, but there are plenty of things that you can control so that you enter ketosis as quickly as possible.
The symptoms of the keto induction phase
What symptoms can you expect during your keto diet induction phase? 
The truth is that keto flu affects everyone differently. Where some people experience fatigue or headaches, others will not. You will definitely experience some symptoms, but your experiences may differ from someone else, even if they are following the same diet.
Common keto induction symptoms include:
- Fatigue
- Headache
- Irritability
- Difficulty focusing (“brain fog”)
- Changes in taste and smell
- Lack of motivation
- Dizziness
- Constipation
- Sugar cravings
- Nausea
- Muscle cramps
- Insomnia
- Increased urination
- Dehydration
- Muscle cramps
- Fruity breath
- Strong-smelling urine
- Stomach Pain
How to make keto induction faster and easier
Like any uncomfortable process, it makes sense to try and get through keto induction as fast as possible. After all, the sooner you get into ketosis, the sooner your keto flu symptoms will disappear, and the quicker you’ll turn into a fat-burning, weight losing machine!
Here are four ways to get through your keto induction phase as fast as possible.
Taper your carb intake before you start your keto diet – because keto is a very low carbohydrate diet, a lot of people binge on carbs before they start. After all, they’ll have to give up bread, rice, pasta, potatoes, cake, cookies, crisps and soda once they start their diet. Why not enjoy these foods before they are off the menu?
Unfortunately, binging on carbs before you start your diet means your glycogen stores will be filled to the brim, and that means it will take longer to deplete them. This will prolong keto induction and the keto flu.
Instead, skip the carb binge and gradually start reducing your carb intake a week or so before you begin your diet. This means you’ll start your keto diet with depleted glycogen stores and will enter ketosis much sooner and more easily.
Stay active – muscle glycogen is your body’s preferred source of energy during physical activity. Each muscle is loaded with glycogen, and that glycogen is for the muscle in which it is stored. That means the glycogen in your legs is for your legs, and the glycogen in your arms is for your arms.
Deplete your glycogen stores faster by getting up, heading out, and doing some physical activity or exercise. Choose things that use large muscle groups working together. This is the fastest way to tap into your glycogen stores. Good options include exercises like burpees, power cleans, and thrusters, and activities like shoveling snow, chopping wood, washing your car by hand, or hiking with a heavy backpack.
The more active you are, the faster you will deplete your glycogen stores.
Use supplements – some supplements can help release glycogen from your muscles to make it easier for your body to use for energy. Because you aren’t eating many carbs, these stores will not be replaced, and that means you will enter ketosis faster. These types of supplements are called glucose dispersal agents. Some of the best options include:
- Alpha lipoic acid (ALA)
- Conjugated linoleic acid (CLA)
- Cinnamon
- Chromium
- MCT (medium chain triglyceride) oil
- Exogenous ketones
- L-carnitine
- L-glutamine
- Magnesium
You don’t have to use all these supplements but choosing just a couple could help make keto induction more tolerable.
Try fasting – going without food for several hours will help you enter ketosis faster. When you don’t eat, your body starts preparing for famine by releasing liver glycogen and using it for energy. In fact, a lot of people go into ketosis between dinner and breakfast, i.e., overnight.
Speed up keto induction by skipping a few meals. For example, eat your evening meal at 8pm, and then do not eat again until the following lunchtime. Alternatively, skip breakfast and lunch and only eat 1-2 meals toward the end of your day. Skipping even a single meal will help speed up glycogen depletion and get you into ketosis sooner.
Eat more fat – healthy fats like coconut oil, avocado oil, and olive oil can help get you into ketosis sooner. Despite containing a lot of calories, in the absence of carbs, your body will quickly start using ketones for energy if you maintain a higher fat intake.
In studies, dieters who eat more fat achieve ketosis faster than those that eat less, even if their carb intake is the same. Make sure at least 60% of your calorie intake comes from fat, and during induction, consider upping that to 80% or even 90%. All-fat meals are called fat fasts and are an accepted way to get into ketosis faster.
How do you know you’re in ketosis?
Getting into ketosis is a process, but it’s inevitable if you eat less than 50 grams of carbs per day. You’ll need to exercise some willpower to ignore the inevitable carb cravings associated with keto induction but, if you tough it out, you’ll be rewarded with faster fat burning and easier weight loss.
Once your glycogen stores are depleted and you enter ketosis, you will notice several significant changes…
- Your hunger disappears
- Your energy levels return and even increase
- You start losing weight
- Your breath might smell a little fruity
- Your concentration and memory improve
- You continue losing weight quickly and easily
You can also confirm that you are in ketosis by using a ketone urine testing strip. These strips, which are cheap and readily available from pharmacies, detect ketones in your urine. Pass the test end of the small paper strip directly through your urine stream (alternatively, collect urine in a clean, dry container and dip the strip in afterward). Shake off any excess, then wait 15 seconds.
If you’re in ketosis, the strip will change color from its original beige to purple. Compare the color to the guide on the side of the bottle to find out how “deep” your level of ketosis is. Deeper purples generally indicate higher levels of ketones.
Bottom Line
Keto induction is not something you want to have to keep going through over and over again. Once you make it into ketosis, it’s probably best to try and stay there. Even just one day off your keto diet will kick you out of ketosis and means you’ll have to go through at least a few keto flu symptoms before you make it back into your fat-burning zone.
Knowing how hard keto induction can be, it makes sense to avoid having to get back into ketosis. Remember too that, if you aren’t in ketosis, you won’t be burning fat as fast as usual. Why delay weight loss if you don’t have to?
Keto induction can be tough for some people, but it’s over faster than a lousy vacation. Being overweight and addicted to carbs and sugar can take years off your life, and a couple of weeks of discomfort is a small price to pay for restoring your health and losing weight once and for all. Use the information in this article to make keto induction as quick and easy as possible.
