Cyclical Ketogenic Diet: Benefits, Cons and How to Start

The keto diet promotes several health benefits, including weight loss and improved metabolic health, making it popular among individuals looking for diet regimens. Due to its popularity, several variations have emerged, including the cyclical keto diet.

This article will discuss everything you need to know, from its definition and benefits to its downsides and how to follow it.

Key Takeaways:

• The cyclical ketogenic diet (CKD) is a variation of the standard keto diet that allows refeeding or carb-loading days (1-2 days weekly).
• The main goal of CKD is to replenish muscle glycogen stores to facilitate muscle growth and boost athletic performance.
• Before getting into CKD, you must first be fat-adapted to switch back to ketosis quickly.
• Focusing on nutrient-dense sources of carbohydrates instead of refined carbs can help maintain overall health.
• Intermittent fasting after the refeeding days helps you get back into ketosis quicker.

Table of Contents:

• What Is the Cyclical Ketogenic Diet?
• Cyclical Ketogenic Diet vs. Carb-Cycling
• Benefits of the Cyclical Ketogenic Diet
• Potential Downsides of a Cyclical Keto Diet
• How to Follow a Cyclical Ketogenic Diet
• How Fast Will You Return to Ketosis?
• Should You Try The CKD?

What Is the Cyclical Ketogenic Diet?

The cyclical ketogenic diet (CKD) involves alternating cycles of low-carbohydrate intake with designated periods of higher carbohydrate consumption.

CKD is a variation of the standard keto diet, but unlike the consistent carb restriction of the standard keto diet, CKD introduces a cyclical pattern, switching from and to ketosis and glycolysis.

In practical terms, individuals following CKD typically adhere to a strict low-carb, high-fat, and moderate-protein diet during most of the week (5-6 days).

This initial phase induces nutritional ketosis, wherein the body predominantly utilizes fats for fuel, producing ketone bodies as a byproduct.¹

The distinctive feature of the cyclical ketogenic diet emerges during specific timeframes, often designated as “refeeding” or “carb-loading” periods (1-2 days).

These windows of time involve a deliberate and controlled increase in carbohydrate intake, temporarily shifting the metabolic state from ketosis to glycolysis to restore glycogen stores.

Here’s a quick look at how the macro ratios look like for the cyclical ketogenic diet:

	SKD	CKD (Keto Days)	CKD (Refeeding Days)
Carbohydrates	5-10%	5%	50-60%
Protein	15-25%	15-25%	15-20%
Fat	70-75%	70-75%	25-30%

The amount of macros you need depends on your daily caloric intake. You have to follow the recommended macro ratio as shown above.

The cyclical ketogenic diet is often popular among athletes wanting improved exercise performance or those who aim for muscle growth and maintenance.

Cyclical Ketogenic Diet vs. Carb-Cycling

The cyclical ketogenic diet and carb-cycling, though both involve the strategic manipulation of carbohydrate intake, diverge in their primary objectives and structural approaches.

With CKD, the primary goal is to fill up glycogen stores for better exercise performance and to get back to ketosis as quickly as possible after the refeeding. On the other hand, carb cycling does not aim for ketosis; it just aims to reduce carb intake in some days.

With carb cycling, the drop in carb intake is not enough to encourage ketosis, as the most common macro ratio follows 40% carb intake on high-carb days (1-3 days) and 20% carb on low-carb days (4-6 days).

Moreover, another difference is the focus on maintained protein intake on both days at 40% in carb cycling, compared to the focus on high fat intake in the cyclical ketogenic diet.

Benefits of the Cyclical Ketogenic Diet

May Boost Athletic Performance

One prominent benefit of the Cyclical Ketogenic Diet (CKD) is its potential to enhance athletic performance.

The cyclical nature of CKD, involving strategic refeeding with carbohydrates, aims to replenish glycogen² stores in muscles, providing a readily available energy source for high-intensity workouts and preventing fatigue.

However, it’s important to note that people who do not engage in high-intensity exercises may not need to do the cyclical ketogenic diet, as they may have difficulty getting back into ketosis due to lack of energy usage.

May Aid in Muscle Gain

CKD’s potential to aid muscle gain stems from the balanced interplay of ketosis and carb refeeding. The ketogenic phases encourage efficient fat utilization for energy, facilitating lean body mass preservation.

On the other hand, carbohydrate increases insulin, which plays a role in protein building, increasing lean body mass,³ and supporting muscle glycogen replenishment.⁴

However, it’s important to note that doing the standard keto diet does not cause a decrease in muscle mass,⁵ and doing the SKD is enough if you do not wish to increase muscle mass.

Weight Management

By combining the fat-burning effects of ketosis with periodic carbohydrate refeeding, CKD may offer a holistic approach to weight control when done right.

The metabolic flexibility fostered by cycling between ketosis and glycolysis may help prevent the metabolic adaptation that leads to weight loss stalls.

May Improve Gut Health

One of the main concerns with the keto diet is the disruption of the gut microbiota⁶ due to the lack of fiber intake.⁷ This often causes diarrhea or constipation.

With the refeeding days of the cyclical ketogenic diet, you can take high-fiber foods, which positively impact the gut. However, it’s crucial to understand that you must get carbs from whole foods to reap this benefit.

May Decrease Keto Symptoms

Adherence to a standard ketogenic diet can lead to decreased glycogen stores, manifesting symptoms commonly referred to as “keto flu,” including fatigue, headaches, and irritability.⁸

CKD’s cyclical design, with periodic carbohydrate reintroduction, may help mitigate these symptoms by providing the body with temporary relief from strict ketosis.

However, it’s important to note that not everyone experiences these symptoms, and these are most likely to happen during the adaptation phase.

Makes Keto Easier to Follow

If you’re someone who wishes to follow keto but currently has a high-carb diet, it would be an easy start to follow the cyclical ketogenic diet due to its cycling approach. Your keto symptoms will decrease, and you will be off to an easy start.

However, if you’re not yet fat-adapted, getting back into ketosis may take a longer time.

Potential Downsides of a Cyclical Keto Diet

Kicks You Out of Ketosis

Due to the high carb intake on refeeding days, you will be kicked out of ketosis. However, this is not the issue but how quickly you get back into ketosis is.

Another issue that may arise from this is overeating and taking unhealthy sources of carbohydrates that will offer lesser benefits than expected.

Possible Weight Gain

The reintroduction of carbohydrates during refeeding periods can increase overall calorie intake, potentially resulting in weight gain, particularly if these cycles are not meticulously planned or if individuals overconsume during high-carb phases.

Increased Water Weight

For every gram of glycogen stored, the body retains 3 grams of water,⁹ leading to temporary water weight gain. This phenomenon can be misleading for those monitoring weight fluctuations, potentially causing frustration or misinterpreting progress.

How to Follow a Cyclical Ketogenic Diet

1. Be Fat-Adapted First

Before embarking on CKD, it’s imperative to establish a solid foundation of fat adaptation.

This entails spending a significant period adhering to a standard ketogenic diet, allowing the body to efficiently utilize fats as the primary energy source and fully adapt to the state of ketosis.

A good rule of thumb is to stay in ketosis for at least a month before doing the CKD. This will allow the body to shift back into ketosis after the refeeding more quickly.

2. Follow Proper Refeeding Timing

Timing is critical for CKD to maximize its benefits and mitigate potential downsides. You have to choose which days you do the keto phase (5-6 days) and refeeding phase (1-2 days) and stick with it.

Moreover, during the refeeding days, you can decide to save all your carb intake into one meal of your choice. This will allow the body to switch back into ketosis faster.

3. Focus on Healthy Carbs

During the refeeding phases, the emphasis should be on incorporating healthy and nutrient-dense carbohydrates.

Opt for complex carbohydrates sourced from whole foods such as high-fiber vegetables and whole grains instead of refined sugars or processed carbs.

4. Manage Carb Intake

During refeeding days, calculate your macros and carefully choose your carbohydrate sources and the serving size.

For instance, if you follow a 2,000 daily caloric intake, you can take up to 300 grams of carbs. During keto days, make sure to stick with the 5% carb allowance to maintain ketosis.

5. Get Back into Ketosis Quickly After Refeeding

Efficiently transitioning back into ketosis after refeeding is vital for maintaining the cyclical rhythm of CKD. Implementing strategies such as intermittent fasting or high-intensity exercise, post-refeeding can expedite the body’s return to ketosis.

How Fast Will You Return to Ketosis?

The direct answer to this is that it depends. For those who are strictly implementing the recommendations for CKD, it may just take them a day to get back into ketosis after intermittent fasting.

However, this varies per individual, and here are the factors you need to take into consideration:

• Individual Metabolic Rate: Metabolic rate varies among individuals. Those with a faster metabolism may transition into ketosis more rapidly than those with a slower metabolic rate.
• Physical Activity: Engaging in physical activity, especially high-intensity exercise, can expedite the depletion of glycogen stores¹⁰ and the return to ketosis. Exercise helps the body utilize glucose more efficiently.
• Overall Diet Composition: The macronutrient composition of the entire diet, not just the refeeding phase, can influence ketosis. Maintaining a high-fat, moderate-protein, and low-carb ratio outside the refeeding period aids in a smoother transition.
• Insulin Sensitivity: Insulin sensitivity varies among individuals. Those with higher insulin sensitivity may return to ketosis more quickly,¹ as their bodies respond more efficiently to changes in carbohydrate intake.
• Fasting or Intermittent Fasting: Implementing fasting or intermittent fasting strategies post-refeeding can enhance the transition to ketosis.¹¹

Should You Try The CKD?

If you want to increase muscle mass and are engaged in high-intensity exercises, needing to replenish glycogen stores occasionally, CKD may be a good option.

However, if you want the benefits of keto, you can stick to the standard keto diet, as it does not cause a decrease in exercise performance or muscle mass.

Consider your goals and weigh the benefits of each keto variation before getting into one.

Frequently Asked Questions (FAQ)

References

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²Jensen, J., Rustad, P. I., Kolnes, A. J., & Lai, C. (2011). The Role of Skeletal Muscle Glycogen Breakdown for Regulation of Insulin Sensitivity by Exercise. Frontiers in Physiology, 2. https://doi.org/10.3389/fphys.2011.00112

³Figueiredo, V. C., & Cameron-Smith, D. (2013). Is carbohydrate needed to further stimulate muscle protein synthesis/hypertrophy following resistance exercise? Journal of the International Society of Sports Nutrition, 10, 42. https://doi.org/10.1186/1550-2783-10-42

⁴Alghannam, A. F., Gonzalez, J. T., & Betts, J. A. (2018). Restoration of Muscle Glycogen and Functional Capacity: Role of Post-Exercise Carbohydrate and Protein Co-Ingestion. Nutrients, 10(2). https://doi.org/10.3390/nu10020253

⁵Paoli, P. A., Cancellara, P., Pompei, P., & Moro, T. (2019). Ketogenic Diet and Skeletal Muscle Hypertrophy: A Frenemy Relationship? Journal of Human Kinetics, 68, 233-247. https://doi.org/10.2478/hukin-2019-0071

⁶Rew, L., Harris, M. D., & Goldie, J. (2022). The ketogenic diet: Its impact on human gut microbiota and potential consequent health outcomes: A systematic literature review. Gastroenterology and Hepatology From Bed to Bench, 15(4), 326-342. https://doi.org/10.22037/ghfbb.v15i4.2600

⁷National Research Council (US) Committee on Diet and Health. Diet and Health: Implications for Reducing Chronic Disease Risk. Washington (DC): National Academies Press (US); 1989. 10, Dietary Fiber. Available from: https://www.ncbi.nlm.nih.gov/books/NBK218764/

⁸Batch, J. T., Lamsal, S. P., Adkins, M., Sultan, S., & Ramirez, M. N. (2020). Advantages and Disadvantages of the Ketogenic Diet: A Review Article. Cureus, 12(8). https://doi.org/10.7759/cureus.9639

⁹Fernández-Elías, V. E., Ortega, J. F., Nelson, R. K., & Mora-Rodriguez, R. (2015). Relationship between muscle water and glycogen recovery after prolonged exercise in the heat in humans. European journal of applied physiology, 115(9), 1919–1926. https://doi.org/10.1007/s00421-015-3175-z

¹⁰Murray, B., & Rosenbloom, C. (2018). Fundamentals of glycogen metabolism for coaches and athletes. Nutrition Reviews, 76(4), 243-259. https://doi.org/10.1093/nutrit/nuy001

¹¹Kerndt, P. R., Naughton, J. L., Driscoll, C. E., & Loxterkamp, D. A. (1982). Fasting: The History, Pathophysiology and Complications. Western Journal of Medicine, 137(5), 379-399. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1274154/