Will One Cheat Day Ruin Ketosis?
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The ketogenic diet has been gaining popularity in recent years. It’s a low-carb, fat-burning diet that strictly reduces carb intake to allow the body to enter ketosis and burn fat for energy.
But how important is it to stay in ketosis all the time? Will one cheat day ruin ketosis?
If you’re on keto, you may be wondering if you have a cheat day for special events, holidays, or even if you’re just craving carbs.
We share with you how a cheat day can ruin ketosis, how long it takes to get back into ketosis, and how to indulge in keto the right way!

What is a Cheat Day?
Cheating on a diet plan involves permitting yourself to temporarily break strict diet rules. It is a reward-based strategy that allows you to indulge in what is restricted on your diet for a brief period.
On the ketogenic diet, a cheat day means temporarily allowing yourself to consume more carbs than you usually would. Including high-calorie foods that wouldn’t otherwise be permitted on a typical diet plan.
Will One Cheat Day Ruin Ketosis?
The short answer is yes. Even just one cheat day can instantly kick you out of ketosis. A cheat day may kick you out of ketosis, but it won’t necessarily cause weight gain. Carbs do not cause weight gain, but too many calories will.
Because it does take a bit of time and effort to get into this metabolic state, to begin with, you’ll have to be prepared to work harder to get it back. This is why we don’t recommend cheat days early in the keto diet.
Check out this video for more information:
Something to be aware of is that indulging in high-carb foods again is likely to bring back your cravings. And transitioning into ketosis again can mean going through those keto flu symptoms again. It can be harder for you to combat the feelings of grogginess and discomfort.
Being out of ketosis also means you’re not reaping the benefit of the fat-burning part of the keto diet. So, depending on why you are doing keto, your goals may be hindered by cheating on your diet.
Imagine working hard to get your body adapted to the diet, having to experience the keto flu, use exogenous ketones, and restrict carbs, only to be lured by pizza and put all your efforts to waste.
To learn if you’re out of ketosis you will need to test your ketone levels. Take note that the number of carbs needed to kick you out of ketosis depends on the individual and how long you’ve been doing keto.
But any high-carb meal over your recommended limit has the potential to knock you out of ketosis.
There are also some other impacts of having a cheat day on the keto diet.
Cheat Days Affect Your Cravings
A keto cheat day affects your cravings which then affects your willingness to adhere to the diet.
Remember that your body naturally wants carbs for its energy, and once they’re reintroduced through a cheat day, your body will start depending on them again instead of ketones.
Your Blood Sugar Levels Will Increase
The keto diet helps you stabilize your blood glucose, but a cheat day could cause these levels to spike. The diet has a lot of benefits, but you may not see them if you have too many cheat days.
A cheat day can even be more dangerous if you have diabetes or digestive issues.
Most people go on the keto diet simply for weight loss, but cheat days for those with illnesses may negate the effects of the diet in controlling seizures, blood pressure, and more.
You’ll Experience the Keto Flu Again
Fatigues, headaches, lethargy, and bloating are just some of the many symptoms of the keto flu.
At the start of the diet, the transition phase can be difficult as your body adapts to burning fat instead of glucose. If you have a cheat day too soon, you’ll experience this all over again.
How Long Does It Take to Get Back in Ketosis?
The amount of time it takes to get back in the state of fat-burning or ketosis depends based on the individual, but it generally takes three days to a week.
It depends on your body’s ability to re-adapt and on the level of carb restriction you choose to do.
If you restricted carbs to the maximum and then introduce carbs again suddenly, then it can take longer for your body to get back in ketosis. The same goes for eating too many carbs on a cheat day.
As mentioned, the body stores glucose as energy, so the more you have stored, the longer it will take you to burn it off and get back in ketosis.
How to Cheat on Keto The Right Way
We are humans, not robots. It can be difficult to perfectly stick to a strict diet such as keto. In fact, studies show that cheating on your diet may have psychological benefits like reduced cravings and the ability to stick to your meal plan better.
So how do you maintain a balance between having a cheat day for motivation and staying in ketosis? The best way is to eat keto-approved cheat meals.
If you’re craving something specific, try looking for keto-friendly substitutes to satisfy yourself! You can find a recipe for a ketogenic version of just about any popular meal you can think of to keep you on course.
Another way to cheat properly is to have a cheat meal instead of a cheat day. Remember, on keto, you can still eat small amounts of carbs depending on your recommended daily macro intake, so try to make the most of your daily allowance.
Besides, it’s easier to stay in ketosis with a cheat meal instead of indulging in an entire cheat day.
So, Should You Cheat on Keto?
Having a cheat day on keto is a surefire way to get knocked out of ketosis. It ruins all your efforts in restricting carbs, weathering the keto flu, and more.
Cheat days can also cause your blood sugar levels to spike, and this could be detrimental if you have diabetes. It will also affect your cravings and make you re-experience the keto flu.
But we are not robots. We cannot always control what our body wants and we often give in to temptation anyway.
To maintain a balance between satisfying our cravings and staying in ketosis, look for keto-friendly substitutes to your favorite high-carb treats.
Find a keto version of the foods you want, indulge in them occasionally, regularly test your ketone levels, and think cheat meals instead of cheat days!