How Long Does It Take to Get Into Ketosis? The Complete Guide

Keto is the most Googled food-related topic in the world, and the keto diet market will be worth $15.6 billion by 2027. It’s continued to grow since being introduced as a way to treat epilepsy years ago.

Keto dieting is now reported to help treat a variety of ills, such as diabetes and fatigue, but its primary use is weight loss. It achieves all these purposes by putting the body in a state known as ketosis.

One of the main questions new dieters have is, how long does it take to get into ketosis? How many days will I have to undertake rigid dieting before I experience results?

There is no single answer to a question like this because the keto diet affects everyone differently. There are ways to get a rough estimate of how long it will take to begin the cycle.

Read our guide to learn what ketosis is, how to enter it, how long it takes, and how to know you’re in it.

What Is Ketosis?

Ketosis occurs when the body uses stored fat for energy instead of dietary carbs. Restricting your intake of carbohydrates causes your body to run out of glucose. Once your liver responds by producing ketones from stored fat cells that your brain can use for energy, you are in ketosis.

Knowing how to get into ketosis is essential for new dieters. Try to eat no more than 50 grams of carbs each day. You should also try to get approximately 70% of your calories from fat, 15% from protein, and 5% or less from carbohydrates.

Maintaining these numbers requires planning your meals and looking at food labels to see how much of each nutrient is in a serving. It takes extra effort, but it’s worth it for the health benefits it provides.

There are certain foods to eat and stay away from if you want to maintain these levels. Non-starchy vegetables, meat, seafood, dairy, and some berries and fruits are great options. Avoid grains, rice and pasta, alcohol, starchy vegetables, and sugary fruits.

Ketosis is the key to the keto diet. Check out this keto diet introduction for more information.

How Long Does It Take to Get Into Ketosis?

There is no single answer to the question of how long does it take to enter ketosis. It differs based on a range of factors.

The average diet before switching to keto has a major effect on how long it takes to reach ketosis. Eating carbs leads to a buildup of glycogen, and if you do it often, it’ll take your body longer to run out of them and rely on ketones for energy.

Activity level is another factor because it affects the amount of energy a body needs. Those who exercise regularly need more energy to sustain themselves, so their bodies are more likely to enter ketosis more quickly to provide it.

Age is a factor because it helps determine the speed of your metabolism. Your entire body slows down as you age and won’t be able to enter ketosis as quickly.

Cheating on a diet is almost mandatory, but the fewer carbs you ingest, i.e. the closer you stick to keto regulations, the sooner you may enter ketosis. There is also evidence to support adding intermittent fasting to your routine for even faster results.

The average person who eats 20-50 grams of carbs per day takes 2-4 days to reach ketosis. The exact timeframe varies from person to person because every body and diet plan is different.

If you do cheat on a keto diet, don’t worry. It may take only 1-3 days of dedicated effort combined with extra help such as intermittent fasting or exogenous ketones to get you into ketosis again. The exact amount of repair time will probably be exactly as long as it took you to get into ketosis the first time.

How Do I Know If I’m In Ketosis?

Those who begin a new keto diet may become impatient if they don’t see immediate results. They may want to know exactly when they’re in ketosis as proof that the process isn’t a waste of their time.

There are ways to get a more exact answer to the question of how long to reach ketosis. You can look for specific symptoms or get your ketone levels tested.


Ketosis changes the way the entire digestive system functions and how it processes food. At first, this can lead to an unpleasant sensation known as the “keto flu.” Symptoms include:

  • Fatigue
  • Headaches
  • Nausea
  • Brain fog
  • Dizziness and feeling faint
  • Stomachaches

These effects are your body’s natural reaction to a new source of energy and should go away within six weeks. After that, you should notice more positive effects of a keto diet, such as:

  • Increased energy
  • Improved sleep
  • Decreased appetite
  • Improved mood
  • Weight loss


The increased presence of ketones in the blood or urine is an obvious sign of ketosis. You can easily get tested for this.

Going to an official lab may provide the most accurate results, but at-home urine and blood tests are also available. Your readings should be between 1.5-3.0mmmol/L and your urine should be dark to indicate dietary ketosis.

A breath meter can measure the level of a specific type of ketone known as acetone in your body. This is another definitive way to medically test if you’re in ketosis.

Where Can I Learn More?

The answer to a question like how long does it take to get into ketosis is deeply personal. It depends on your individual body and nutritional needs.

Anyone can enter ketosis by limiting their intake of carbohydrates and forcing their body to rely on ketones for energy instead. There is no guarantee that this will happen quickly and could take days or weeks.

There are ways to tell if you are currently in ketosis. You can try to spot symptoms of the keto flu or positive effects it’s having on your body. You could also use professional or at-home tests.

You need to do your research before trying any new diet, especially one that affects your body as powerfully as keto. Read the rest of our content for answers to any more questions you have about this popular method.

Leave a Reply

Your email address will not be published. Required fields are marked *