How Long Does It Take to Get Into Ketosis?
A ketogenic diet is high-fat, low-carb, and moderate in protein.
It primarily involves replacing most of the carbohydrates in the diet with fat.
In a sense, this tricks the body into thinking it is in a fasting state and it begins to utilize fat stores and ketones as primary fuel sources, instead of glucose.
This metabolic shift towards fat burning and producing ketones is called ketosis.
If you’ve just started a ketogenic diet you’ve got wondered how long it will need to get involved with ketosis.
The answer isn’t as clear as you may realise while there is a ton of factors that affect how long it takes to enter ketosis.
How Long Does It Take to Get Into Ketosis?
Before starting on a keto diet, there are many boxes to check.
First, verify with your physician it’s safe for you to be on a ketogenic diet considering your medical and medication history.
Second, talk to a nutrition professional to help you plan a well-formulated ketogenic diet that meets your nutritional needs.
To make sure your diet meets your macro and micronutrient needs, a dietitian will keep in mind your:
- Body composition
- Physical activity level
- Overall health
- Weight loss goals, etc.
Additionally, they can evaluate your labs, and help you manage any side effects.
How long it takes to achieve and maintain a state of ketosis is highly individualized. Some people enter ketosis fast, inside of 2 days.
For others, getting into ketosis takes longer.
Ketosis can have many things: your carb intake, fat intake, protein intake, overall diet, energy needs, exercise, stress, sleep, and body composition.
Probably the most significant factors that affects the time it takes to get involved with ketosis is your carbohydrate restriction.
The carbohydrate restriction needed to enter ketosis and how long it takes to get involved with ketosis varies from person to person.
In case you are only starting on a keto diet it is first of all more carbs and decrease the amount for days until you enter ketosis.
This helps your body adjust to ketosis faster with minimal side effects.
If your body is used to 200-300 grams of carbs per day, it becomes a huge shock to all of the sudden switch to 30 grams per day.
A better plan is to start somewhere around 100 grams, then work down to 75 grams, and eventually work down to 50 grams of carbs per day.
You will probably find this is a good enough restriction to see results.
How to Test for Ketones
The most reliable and accurate way of checking if you’re in ketosis is to measure ketone levels in the blood.
Blood Glucose Meter Testing
They can do this by using a blood glucose meter that is designed to test for ketone levels.
A person in nutritional ketosis will have blood ketone levels of 0.5 to 3 mg/dL (1).
Urine and Breath Testing
You can also use urine and breath tests to check ketone levels but these methods are less reliable than blood tests.
Blood, urine, and breath tests can be done at home or in a doctor’s office.
Signs That You’re in Ketosis
There’s no need to test for ketone levels to be on a ketogenic diet.
There are a few common indicators that may indicate that you’re in ketosis. Some people experience mild symptoms like bad breath and irritability.
Others experience the “keto-flu” as their body adapts to nutritional ketosis.
The symptoms of the “keto-flu” are constipation, headache, bad breath, muscle cramps, diarrhea, general weakness, and rash (5).
These adverse effects should not last more than 1-2 weeks.
Staying hydrated and getting enough electrolytes will let you avoid some or these negative symptoms.
Once your body adjusts to nutritional ketosis, you should notice an increase in positive effects, such as reduced hunger cravings, weight loss, and over time, an improvement in energy.
The time it takes to purchase ketosis is different for everybody. It usually takes 2 days for one person to enter ketosis, while it takes 10 days for another person.
Various factors affect how long it takes to purchase ketosis, such as body composition, metabolism, age, physical activity, energy needs, macronutrient intake, etc.
It also takes time for the body to adjust once you’re in ketosis. It usually takes anywhere from 1 to 4 weeks. Many people experience symptoms that are known as the “ keto flu.”
These adverse symptoms are usually temporary, but ought to reported to the person that is overseeing your diet.
You could probably avoid these adverse symptoms by giving your body time to sit in the metabolic shift into ketosis.
Also, staying hydrated and getting enough electrolytes can help you avoid the symptoms of the “ keto flu.”
Please note that In the short-term, nutritional ketosis is considered safe, however, there is limited research on the long-term effects.
This is the reason it is recommended to eventually transition to a sustainable, nutrient-dense, low-carb diet.
Certain groups of people are advised not to follow a ketogenic diet, including people with: type 1 diabetes, pancreatic disease, liver conditions, thyroid problems, eating disorders, gallbladder disease, pregnant or breastfeeding women, and athletes. Always check with your doctor or dietitian first to help it become safe so you might start a keto diet.