It depends.
- How long have you been in ketosis for before your cheat meal/day?
- What did your cheat meal/day consist of?
- Do you exercise regularly?
- Did you quickly get into ketosis when you first started keto dieting?
- Will you be intermittent fasting?
- Did you drink alcohol or beer?
Your answer to these questions impacts how long it will take you to get back into ketosis.
In general, you will probably be back in ketosis within the next 24 to 48 hours if one or more of the following applies to you:
- You were in ketosis for around a month or longer before cheating on the diet.
- You are doing an extended intermittent fast (>16 hours) beginning after your last cheat meal.
- You exercised on the day of and/or after your cheat day.
- You got into ketosis quickly when you first started the keto diet.
- You didn’t go too far over your carb limit with your cheat meal.
On the other hand, if you haven’t even had a chance to adapt to keto yet, you are sedentary, you had multiple cheat meals, and/or your body struggled to adjust to keto dieting at first, then it may take you longer than two days to get back into ketosis.
Keep in mind that these estimates are based on theory and should be used as a framework to understand what factors matter when it comes to getting into ketosis as quickly as possible after a cheat meal/day.
Overall, you can get back into ketosis as soon as 12-16 hours after your last cheat meal (with the help of fasting and exercise) or it can take as long as it did when you first started keto.
If you’d like to get a better understanding of ketosis, check out our recent article on the topic.