Staying On Track: One Bad Day On Keto

If you're on the keto diet, you might be wondering if you can take a day off to enjoy your favourite carb-y foods. But will one cheat day knock you out of ketosis and ruin all your progress?

The short answer is yes, you will fall out of fat-burning mode. The amount of time it takes to get back into that coveted fat-burning zone will vary based on the person, but it generally takes one to three days. However, this doesn't mean that you need to forego your keto diet for a temporary binge, and it's important to determine whether a specific diet fits your lifestyle.

If you're looking to stay in ketosis, it's best to opt for keto-friendly substitutes to curb your cravings and save true cheat meals as a last resort. You can also have cheat meals instead of full cheat days, as it's much easier to stay on top of your overall nutrition and calories. If you do decide to have a cheat day, it's a good idea to count your calories and carbs and stay at a caloric deficit.

Ultimately, the reality is that highly restrictive diets may be successful in the short term but are difficult to sustain in the long run. It's important to take a moderate approach when it comes to healthy eating to avoid going overboard or becoming frustrated due to feeling overly restricted.

You will fall out of ketosis

Falling out of ketosis is one of the consequences of having a cheat day on the keto diet. Ketosis is a state your body goes into when it uses fat to create molecules called ketones. This happens when there is not much sugar around for your body to use as energy. If you eat less than 50 grams of carbohydrates per day, your body will use up its glycogen stores for energy.

When you introduce carbs into your diet, even for a single day, you will no longer be in ketosis. Eating above 50 grams of carbs for your cheat day will very likely take you out of ketosis. Starches and sugars both create a spike in blood sugar levels. Since your body naturally prefers to use carbohydrates for energy, it will rapidly begin using the available carbs as its primary source of fuel rather than fat.

The main problem with dropping out of ketosis is getting back into it. After a cheat day, it can take a few days and even up to a week to get back to using fat for fuel. That means that a single cheat day will really impede your progress for up to seven days.

The amount of time it takes to get back into ketosis will vary based on the person, but it generally takes one to three days. If you’re used to restricting to a maximum—and then suddenly introduce carbs—it could take longer to get back into ketosis. Likewise, if you eat a ton of carbs on a cheat day—rather than just a few extra grams—it may also take a little extra time.

You may also experience "keto flu" symptoms again, depending on your metabolism and what kind of keto break you took. You might experience headaches, nausea, fatigue, stomach pain and body aches, brain fog, and mood swings. These should go away quickly as long as you don't bump yourself out of ketosis again.

You may experience keto flu symptoms again

If you've been on the keto diet for a while and then have a cheat day, you may experience a recurrence of keto flu symptoms. This is because the keto diet is a significant shift in how your body produces energy, and it takes time to adjust. When you introduce carbs back into your system, your body has to readjust, and this can trigger a range of unpleasant symptoms.

Keto flu symptoms can include fatigue, headaches, low energy, nausea, stomach pain, body aches, brain fog, and mood swings. These symptoms are usually temporary and should go away within a few days as your body readjusts to the keto diet. However, it's important to note that everyone's experience with keto flu may vary, and some people may find it more challenging to get back into ketosis after a cheat day.

To minimize the impact of keto flu, it's essential to ease back into the keto diet gradually and ensure you're staying hydrated and getting enough electrolytes. Some people also find that supplementing with exogenous ketones can help alleviate keto flu symptoms.

It's worth noting that cheat days are not recommended by all experts. Some believe that they can lead to an unhealthy relationship with food and make it harder to stick to the keto diet in the long run. Ultimately, it's up to you to decide if the potential benefits of a cheat day are worth the risk of experiencing keto flu symptoms again. If you do choose to have a cheat day, it's crucial to listen to your body and give it the time it needs to readjust to the keto diet.

It could take a few days to a week to get back into ketosis

To get back into ketosis more quickly, you can restrict carbs even more than you normally would and increase your exercise. This will help deplete glycogen stores and get your body back to using fat for fuel. However, the best course of action is to not worry too much about getting back into ketosis quickly and just get back on your keto plan. With anything diet-related, a more measured approach is usually better than going to extremes.

It's important to note that cheat days are not recommended for everyone, especially those using the keto diet for medical reasons. If you find that cheat days are derailing your progress or making it hard to get back on track, it might be better to avoid them altogether. Ultimately, the keto diet should be tailored to your individual needs and what works for you.

You may experience a sugar crash

If you have one bad day on keto, you may experience a sugar crash. This is when all the glucose is gone from the bloodstream, and you start to feel sluggish and off-kilter. A sugar crash can leave you feeling like your internal circuits are fried, or like a heap of smouldering wires.

The Effects of a Sugar Crash

A sugar crash can cause you to feel tired and less alert. You may feel sluggish, off-kilter, and like your internal circuits are fried. Your immune system may also slow down, and your sleep may be disrupted.

How to Avoid a Sugar Crash

To avoid a sugar crash, it is important to limit your carb intake and calories during your cheat meal. Make sure you don't go overboard with the carbs and that you stay at a caloric deficit. If you can, stick to fewer than 150g of carbs for the day. This will help to minimise the adverse effects and potential weight gain.

How to Recover from a Sugar Crash

If you do experience a sugar crash, don't worry. You will recover and get back into ketosis. The important thing is to remember that one misstep will not obliterate your goals. Your body will allow for fluctuations in carb consumption, and you will develop metabolic flexibility. To get back into ketosis, you need to use up the glucose you consumed and the glycogen your body stored. This can be done by scaling back your carbs, making sure you are getting the correct balance of electrolytes, and consuming sufficient high-quality fats.

You may crave carbs and sugar more

The keto diet is a high-fat, low-carb diet that emphasises weight loss by burning fat. The theory behind the keto diet is that you can shed pounds by slashing the carbs you eat and filling up on fats instead to get your body into ketosis. Ketosis is a state your body goes into when it uses fat to create molecules called ketones.

When you go on a keto diet, you may experience intense cravings for carbs and sugar. This is because your body has to make changes (such as altering specific hormones and increasing enzyme production) to transition to a fat-burning state. Having a regular dose of glucose can prevent your body from becoming fat-adapted. This, in turn, could slow any progress made towards weight loss and fat loss goals (i.e. the reason you started keto in the first place).

By veering away from your keto meal plan and removing your body from a ketogenic state, you may find yourself craving carbs and sugar more than before. Carb and sugar cravings aren't just in your head. They can be signs of addiction. Believe it or not, researchers have compared sugar addiction to cocaine addiction. Sugar may even be more rewarding!

Cheating can strengthen these pathways, making it harder to avoid sugary treats in the future.

How to Avoid Cravings

If you do find yourself craving sweets and carbs, opt for keto-friendly alternatives like at-home keto pizza or already-made keto cookies.

You can also follow a cyclical ketogenic diet, where you only eat a strict keto diet for five days within a seven-day period. Many people choose to eat a standard keto diet during the weekdays and then have a high-carb approach on the weekends. While this will still likely kick you out of the metabolic state of ketosis, following a CKD can make eating keto more mentally manageable for some people.

Cheat Days and Cravings

If you've been on keto for a while and are considering a cheat day, be aware that this could increase your cravings for carbs and sugar. A cheat day can be a welcomed break from the diet, but it's not without its drawbacks, specifically interfering with your state of ketosis. A full cheat day of consuming sugar, bread and pasta will take your body out of ketosis, which may take days to recover from.

How to Enjoy a Cheat Meal on the Keto Diet

Instead of a full cheat day, some people opt for a cheat meal every now and then. You'll likely consume a lower number of carbs than you would on a full cheat day. Plus, in many cases, a single cheat meal won't take you out of a state of ketosis.

"It won't have as much of a negative impact," says Lolita Carrico, a certified nutritionist based in Los Angeles and founder of the keto-based lifestyle website Ketology. "For example, if you want pancakes for breakfast with syrup, enjoy it, but focus on keeping the other meals in the day low-carb and higher in protein and fats."

How to Avoid Cravings After a Cheat Day

If you do decide to have a cheat day, be prepared for the possibility of increased cravings for carbs and sugar afterwards. To get back into ketosis, restrict your carb intake even more than you normally would for a few days. This will help limit the amount of stored glycogen in your body, which will help you turn back to fat for fuel more quickly.

Increasing how much you exercise in the days following your cheat day will also help deplete glycogen stores, which will help you reach a state of ketosis more quickly. Adding 15-20 minutes of medium-to-high-intensity exercise each day after a cheat day should help you get back into ketosis more quickly.

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