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Keto Cheat Days: Experts Share If They'll Actually Derail Ketosis

Does taking one simple cheat day really throw you out of ketosis? Here's what the experts had to say.

The ketogenic diet, commonly known by its nickname, keto, has become widely popular in recent years—and it's not just fitness fanatics and health guru who are doing it anymore. A low-carb, fat-burning alternative, this diet is all about reducing the intake of net carbs in order to enter the body into ketosis. But how important is it to always stay in ketosis? And can you take a keto cheat day?

In ketosis, the body works efficiently to break down fat into ketones that get flushed through urine. Rather than burning the carbohydrates and sugars in the foods you're consuming, in ketosis, your body can focus all of its attention on burning the stored fat, which helps to reduce body weight.

However, ketosis can be a tricky state to stay in, so you may be left wondering just how strict you need to be on your keto diet in order to stay there.

Whether you've committed to the keto diet or are exploring and wanting to learn more, here's everything you need to know about if cheat days are possible on the keto diet, according to the experts.

The positives and negatives of cheat meals

Cheat meals. We all enjoy them, and we're all curious. But what is a cheat meal, especially on the ketogenic diet? And what are the potential effects of getting your body out of ketosis?

The keto diet relies heavily on reducing certain foods from the diet in order to enter ketosis. When these 'restricted' items are re-introduced, (especially in large quantities like they would be in a 'cheat meal'), it can really impact the body's fat-burning state.

While cheat days may sound like a relief from the strict keto diet standards from time to time, they do come with consequences. Here are some of the downsides of having a keto cheat day that you may want to consider before jumping in.

Cheat days kick you out of ketosis

The big (and obvious) downside to cheating on the keto diet is that you'll likely bring yourself out of ketosis.

Because it does take a bit of time and effort to get into that state to begin with, you'll have to be prepared to work harder to get back, plus combat any feelings of grogginess or discomfort that come with eating foods you haven't in a while (which many dieters call the keto flu, which is when you might experience headaches, bloating, or grogginess that result from eating "non-keto" foods).

To see if you're out of ketosis, you'll want to test your ketone levels. While it may feel like a worthwhile gamble—as some foods will kick you out of ketosis and some won't—the majority of cheat meals will negatively affect ketosis.

It's a risk you'll have to weigh out before deciding.

Cheating impacts your fat-burning and cravings

When you're out of ketosis, you're not reaping the benefits of the keto diet—like fat-burning. After working hard to get your body adapted to the new diet, you'll have to decide whether it's worth thwarting those efforts for a few carbs.

A keto cheat day can also cause cravings, which will start to impact your willingness to adhere to the diet in the first place.

Hillary Cecere, RDN for Eat Clean Bro, says, "I would not recommend a cheat day on the ketogenic diet. Carbs are the body's preferred energy system, so if carbs are introduced, the body will use them instead of ketones. Once you are out of ketosis, a ketogenic diet would have to be reintroduced and it may take 2 to 3 days to introduce ketosis again."

Your blood sugar will skyrocket

The keto diet is great for stabilizing blood glucose, but with cheat days, these levels can spike (even dangerously!). Although the diet can have many benefits, these are often void when the diet is broken by cheat meals or binging.

This becomes even more serious if you have diabetes or other digestive issues. Cecere says, "If you are using the keto diet as a weight-loss tool, cheating is not the end of the world, but I would still not recommend it. If you are using the keto diet for a medical reason, like to control seizures, cheating is a definite no."

How to take a keto cheat day the right way

So, after knowing all the potential risks, why would one want to cheat the keto diet?

Sometimes following a more restrictive diet regimen can feel difficult or overwhelming. To combat this, you like to have a cheat meal every once in a while so things feel more doable.

Or maybe there's a specific reason you want to try a cheat meal. Perhaps you're traveling or spending time with non-keto friends and don't want to make ordering for the group difficult. Whatever your reasoning is, you may want to cheat the diet once in a while. You just have to learn to cheat the "right way."

Don't totally eliminate any foods

If you're feeling tempted to binge, or simply having a hard time keeping yourself in ketosis, Dr. Rachel Paul PhD, RD of College Nutritionist, recommends a low-carb diet over keto if you're not willing to strictly adhere to ketosis.

"With a low-carb diet, you get many of the benefits of a low-carb approach, but it's more realistic and doable for the long-term," she says.

Or if you're wanting to stay on keto, rather than a completely restrictive mindset, Paul encourages ideally less than 150 grams of carbohydrates per day, which can include starchy vegetables like potatoes, beans, or peas, or grains like pasta, breads, or quinoa. Even though she is incorporating these carbohydrates into the diet, the quantity is low enough to keep someone in ketosis—without the desire to indulge in that cheat meal.

She also recommends listening to your body more to fight against cravings.

"The first question I want you to ask yourself is, 'Am I hungry for breakfast?' [The phrase] 'breakfast is the most important meal of the day' is just not true for everyone," says Paul. "I generally recommend not eating just for the sake of eating—eat breakfast when you feel true hunger in your stomach."

Beth Lipton, recipe developer and food/wellness writer, offers another approach on 'cheat days,' "Rather than spending your mental energy deciding whether or not to 'cheat' and then feeling guilty, redirect it toward figuring out what works best for you. And that's individual," she says.

Try keto cycles

Another common way to 'cheat' the keto diet is to think of ketosis in cycles rather than a constant state. The Cyclical Ketogenic Diet (CKD) incorporates a week of the standard diet followed by several days of higher carbs. Some dieters will do the standard diet during the week, followed by the cycle on the weekends.

This does bring you in and out of ketosis, which many experts do not recommend. However, the cycle approach can help to make the diet feel more manageable and work to preserve lean muscle mass.

It's not perfect for everyone, though, and some people may or may not have success depending on their body type.

No-sugar-added recipes you'll actually look forward to eating.

Make a keto cheat meal

So who says you can't actually cheat with keto?

One of the simplest (and smartest) ways to have a keto cheat day on keto is to create keto-friendly alternatives or low-carb swaps to the foods you love. For example, if you're craving cheesy pasta, try subbing the noodles with zucchini (zoodles!) instead. Or get a burger and use lettuce instead of a bun.

There are countless keto-friendly recipes that you can incorporate to stay on track but satisfy the cravings.

If you're having crazy cravings, it's also a good idea to consider your protein intake. Protein is a staple to the keto diet, but if you're not getting enough protein, you might be falling victim to cravings that you can easily avoid by adding more meats and vegetables. Sometimes filling your body with the right foods can be the perfect alternative to a cheat day.

It's also a great idea to meal prep so that you have good, diet-friendly foods on hand and feel less inclined to stray.

Bottom line: So is cheating on the keto diet OK?

Cheat days—for any diet—come with risks. When you cheat, you step backward and negatively impact any progress you've made with your diet, which may or may not be worth it depending on what you're trying to achieve or any medical conditions you may have.

Dieting can be hard, though, and if you're craving something, there are ways to satisfy, even when you're on the keto diet.

Experts recommend staying as strict as possible to the diet to prevent adverse effects. However, you can incorporate small amounts of carbs to your diet to make your meals feel more manageable. You can also find keto-friendly cheat meals, like these Keto Latte Swirl Brownies, to indulge in!

Marisa Donnelly
Marisa Donnelly is a writing coach, editor, and freelance food and health writer. Read more about Marisa