Cheat Days And Keto: Friend Or Foe?

The ketogenic diet is a low-carb, high-fat diet that aims to put your body into a metabolic state called ketosis, where it burns fat for energy instead of carbohydrates. While the keto diet can be an effective way to lose weight and improve health, it can be challenging to maintain, and many people wonder if they can take a cheat day to indulge in their favourite high-carb foods without compromising their progress.

Cheat days on the keto diet can have several negative consequences. Firstly, they can kick you out of ketosis, as introducing restricted high-carb foods can disrupt the body's fat-burning state. It can take several days to get back into ketosis, and you may experience symptoms like headaches, bloating, and grogginess, commonly known as the keto flu. Cheat days can also impact your fat-burning abilities and increase cravings, making it harder to stick to the diet. Additionally, cheat days can cause a spike in blood sugar levels, which can be dangerous for individuals with diabetes or other digestive issues.

However, some experts suggest that a strict diet regimen may be challenging to maintain, and occasional cheat meals can make the keto diet more manageable. If you decide to have a cheat day, it is important to limit its extent and severity to minimise interference with ketosis. You can also opt for keto-friendly alternatives or low-carb swaps for your favourite foods. Ultimately, the decision to have a cheat day on the keto diet depends on your goals, discipline, and how your body responds to carb intake.

Cheat days kick you out of ketosis

Cheat days can be a common strategy for strict diets. They allow you to break the diet's rules for a day, or just a single meal. The idea is that by allowing yourself short periods of indulgence, you're more likely to stick to the diet in the long term.

However, cheat days are far from ideal for the keto diet. This is because the keto diet relies on your body staying in ketosis, a metabolic state in which your body burns fat as its primary source of energy instead of carbohydrates. To stay in ketosis, you need to eat fewer than 50 grams of carbohydrates per day. Eating more than this can kick your body out of ketosis.

Because 50 grams of carbohydrates is a relatively small amount, a single cheat meal can easily exceed your daily allowance and take your body out of ketosis. A cheat day is almost certain to surpass 50 grams of carbs. As carbohydrates are your body's preferred energy source, your body will use them over ketone bodies (derived from fats) as soon as they are available.

If you have been on the keto diet for more than 3 to 6 weeks, it will be much easier to go back into ketosis than if you were new to the diet. This is because you are likely getting 70% of your energy from fat, and your body is fat-adapted.

If you do find yourself out of ketosis, you will need to strictly follow the keto diet to re-enter ketosis, which can take several days to a week.

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. "I would not recommend a cheat day on the ketogenic diet, " says Hillary Cecere, RDN for Eat Clean Bro. "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 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 toward weight loss and fat loss goals (i.e. the reason you started keto in the first place).

One study finds that a low-carb, high-fat diet like keto has been shown to reduce appetite and hunger cravings. While it does take an adjustment period to achieve these benefits, once your body becomes fat-adapted, you are less likely to feel hungry and experience sugar cravings throughout the day.

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.

Your blood sugar will skyrocket

Cheat days on the keto diet can cause your blood sugar to skyrocket. The keto diet is great for stabilising blood glucose, but with cheat days, these levels can spike, even dangerously. This is especially serious if you have diabetes or other digestive issues.

When you eat a high-carb meal, your body will switch back to glucose as a source of fuel. This can cause a sugar crash, and you might experience repeat symptoms of the "keto flu", such as headaches, bloating, and grogginess.

If you're following the keto diet for weight loss, a cheat meal is not the end of the world. However, if you're using the keto diet for a medical reason, such as to control seizures or manage blood sugar levels, cheating is not recommended.

To avoid blood sugar spikes, you can try a low-carb diet instead of keto if you're not willing to strictly adhere to ketosis. You can also incorporate small amounts of carbs into your diet, such as starchy vegetables or grains, while still staying within the carb limit to maintain ketosis.

If you do choose to have a cheat meal, be prepared to work harder to get back into ketosis and manage any negative side effects. It can take several days to get back on track, and you may experience cravings that impact your willingness to adhere to the diet.

Cheating causes cravings

Cheating on your keto diet can cause cravings for several reasons. Firstly, reintroducing restricted foods can impact the body's fat-burning state, causing your body to use carbohydrates as fuel instead of ketones. This can lead to a spike in blood sugar levels and a subsequent sugar crash, which can trigger intense sugar cravings.

Additionally, cheating on the keto diet can cause a disruption in ketosis, the metabolic state where the body burns fat for energy instead of carbohydrates. When you consume high-carb foods during a cheat meal or cheat day, your body may exit ketosis. As a result, you may experience increased cravings as your body craves the carbohydrates it was previously restricted from having.

Furthermore, research suggests that the reintroduction of a high-carb meal to a ketogenic diet may damage your blood vessels. This disruption can also contribute to cravings as your body attempts to regulate its fuel source.

To manage cravings, it is recommended to create keto-friendly alternatives or low-carb swaps for the foods you crave. For example, if you're craving pasta, you can substitute zucchini noodles (zoodles) instead. By finding creative ways to satisfy your cravings while staying within the keto diet guidelines, you can reduce the urge to cheat and minimize the impact on your progress.

It is worth noting that while the occasional cheat meal or day may not completely derail your weight loss progress, frequent cheat days can promote unhealthy eating habits and make it more challenging to maintain ketosis. Therefore, it is generally recommended to avoid cheat days and focus on building sustainable long-term eating habits.

You could experience keto flu again

If you choose to eat a high-carb food, know that you could experience the unwanted symptoms of keto flu again. These symptoms include fatigue, headaches, low energy, and bloating. If this happens, supplementing with exogenous ketones may help.

When you eat a high-carb meal, you can experience a nasty sugar hit. If you eat dessert or high-carb food and don't feel well the next day, it's probably best to avoid it.

If you're experiencing a once-in-a-lifetime moment, such as eating Italian pizza in Rome or eating a slice of cake at your grandmother's 90th birthday, then it's your choice as to whether you want to deviate from a strict keto diet.

If you do decide to indulge, know that there are plenty of ways to enjoy these foods, including delicious keto-friendly recipes and keto-friendly alternatives.

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