If you’re new to keto, you might have asked yourself the question, how long does it take to get into ketosis? Research shows that there are real health benefits from achieving this metabolic state. However, getting into ketosis can be challenging especially for those just starting out on keto. In this article, we will explore what ketosis is, its scientifically proven benefits, and answer the question of how long it takes for you to achieve it.
Ketosis Overview
Ketosis is a natural metabolic state that occurs when your body is deprived of carbohydrates. With limited carbohydrate intake (<50g per day), the body eventually runs out of glucose, the main source of fuel.
When this happens, your body begins to use glycogen (glucose stores in the muscles) and when it’s depleted it resorts to breaking down fat into molecules called ketones, which act as an alternative energy source(*, *).
Ketosis offers various benefits, including weight loss, improved blood sugar control, improved insulin sensitivity, increased energy levels, improved cardiovascular health, reduced inflammation, enhanced brain function, and improved physical performance (*, *, *, *, *, *).
How Long Does It Take to Enter Ketosis?
The time it takes to enter ketosis varies from person to person. Different individuals under the same conditions, and following the same lifestyle may not get into ketosis at the same time. Ketosis is influenced by various factors such as diet, age, body composition, physical activity level, and genetics, among others.
The average time to reach ketosis is around two to eleven days, but it can take up to a week or longer for some people(*).
Factors Affecting the Time to Enter Ketosis
Various factors can affect the time it takes you to enter ketosis including:
- Metabolism: Your rate of metabolism determines how quickly the body burns through glycogen stores and switches to fat. Usually, those with a higher metabolic rate will enter ketosis faster than those with a lower metabolic rate. This is simply because a higher metabolic rate means you require more energy in a given timeframe.
- Carbohydrate Intake: The fewer carbohydrates you consume, the faster your body will enter ketosis. Typically, you need to limit your carbohydrate intake to less than 50 grams per day to enter ketosis.
- Fat consumption: Fat intake provides the body with the necessary fat molecules to create ketones, which are used as fuel when carbohydrates are unavailable and can trigger the metabolic state of ketosis.
- Protein Intake: Excessive protein intake can cause your body to convert protein into glucose, which can prevent you from entering ketosis. This is why the ketogenic diet is a moderate protein diet and you should, therefore, closely watch your protein intake as much as you watch your carb intake.
- Physical Activity: Exercise helps to deplete glycogen stores in your muscles, which is necessary for your body to switch to burning fat for energy. However, excessive exercise can increase carbohydrate cravings, which may make it harder to achieve ketosis.
- Age: As you age, your metabolic rate slows down, which means it may take you longer to enter ketosis. However, this is not always the case and varies from person to person.
- Body Composition: People with more glycogen stores might take longer to enter ketosis than those with fewer stores. This is because your body has to deplete the glycogen before entering into ketosis.
- Fasting: Fasting can also help you enter ketosis faster. When you fast, your body uses up its glycogen stores and starts to burn fat for fuel. There are many fasting patterns you can try to achieve ketosis. The most popular is intermittent fasting where you eat nothing for a specific period of time and eat as usual for the rest of the day. For example, for a 16/8 pattern, you will need to fast for 16 hours and eat all your meals within an eight-hour window.
- Lack of Sleep: Lack of sleep can delay the onset of ketosis by affecting hormones that regulate metabolism and glucose levels(*).
- Stress: Stress can elevate cortisol levels, which leads to increased blood sugar levels and insulin secretion, delaying the switch to fat-burning for fuel and the onset of ketosis(*).
How Do You Know If You’re in Ketosis?
The most definitive way to know you are in ketosis is through a blood test. Blood levels of 0.5 to 3 mg/dl indicate nutritional ketosis(*) Other ways to check if you are in ketosis include breath acetone tests, urine ketone testing, and monitoring physical symptoms.
You may experience physical symptoms of ketosis commonly referred to as the keto flu which may include fatigue, increased thirst, headache, nausea, and bad breath (fruity acetone-smelling breath). Some people also report a metallic taste in their mouth, a decrease in appetite, frequent urination, and increased energy levels.
Breath acetone testing involves using a handheld device (breath analyzer) to measure the level of acetone in your breath. Acetone is a byproduct of ketone production, and measuring its level can give you an indication of whether you are in ketosis.
Urine ketone testing, though not as precise as blood ketone testing, still has its advantages and disadvantages. On the plus side, it’s a simple, non-invasive, and cost-effective way to gauge whether you’re in ketosis. However, the accuracy of the results can be affected by factors such as hydration levels, making it less reliable than blood testing.
Tips to Achieve Ketosis
If you are looking to achieve ketosis, here a few that tips can help you get there:
- Reduce Carbohydrate Intake: The most important tip to getting into ketosis faster is to reduce your carbohydrate intake. Consume about 20g-50 g of carbohydrates a day to induce the process(*). This means cutting out sugary and starchy foods such as bread, pasta, and candy. You should also be cautious about hidden sugars in foods such as starchy vegetables, fruits, and soups. Consume whole foods that contain a very low sugar content and high fiber such as green leafy vegetables like spinach, broccoli, kale, and cauliflower.
Increase Fat Intake: In addition to reducing your carbohydrate intake, you should increase your fat intake to about 75% of calories. Consume foods that contain a lot of healthy fats such as fatty fish, cheese, butter, nuts, avocado, and coconut oil. - Incorporate Physical Activity: Incorporating physical activity into your routine can also help you achieve ketosis faster. This is because exercise helps to deplete glycogen stores in your muscles, which is necessary for your body to switch to burning fat for energy. Aim to engage in moderate-intensity exercise for at least 30 minutes per day.
- Intermittent Fasting: This style of fasting involves alternating between eating and fasting for scheduled periods. This can cause your body to use up all its glycogen stores resorting to using fats for energy which can help get into ketosis faster.
Add MCTs to Your Routine: Consumption of 1-3 tablespoons of coconut oil a day can aid in attaining ketosis. Coconut oil is a rich source of medium-chain triglycerides (MCTs), which are easily converted into ketones by the liver helping to achieve and maintain ketosis(*). You can also add MCT oil supplements into your routine. MCT oils provide a concentrated source of medium-chain triglycerides, allowing for a convenient and reliable way to increase your intake of ketone-forming fats. - Measure Your Ketone Levels Regularly: Measuring ketone levels can be a helpful tool for achieving and maintaining ketosis. By monitoring ketone levels, you can adjust your diet and lifestyle to ensure that you are staying in a state of ketosis and optimizing its benefits.
- Be Consistent: Achieving ketosis takes time, and it may take several weeks for your body to fully adapt to this state. Be patient and consistent with your dietary and exercise habits, and trust the process.
The Bottom Line
The time it takes to reach ketosis varies from person to person, typically ranging from two to eleven days. How long you will take to get there depends on several factors such as your carbohydrate intake, physical activity, age, and more. To confirm ketosis, you can monitor physical symptoms or use methods like breath, blood, or urine ketone testing. To maximize your chances of success, consider changes such as reducing carbs, increasing fat, being active, staying hydrated, and getting enough sleep. As always, speak to a qualified healthcare professional before making any significant changes to your diet.