Summary of Ketogenic Diet Plan Combined with Intermittent Fasting
- The case study focused on a 13-week reduced ketogenic diet combined with intermittent fasting with strength training. This comprehensive study aimed to explore the synergistic effects of these dietary approaches on various health parameters.
- The study observed a significant increase in testosterone concentration. This increase was not just marginal; it was almost twofold. Despite the already high values at baseline, the testosterone levels reached 172% above the laboratory limit of normal.
- The study noted significant improvements in body composition, including lower body mass, body mass index (BMI), and adipose tissue amount, as well as a greater percentage of lean body mass, muscle mass, and water in the body.
- While the study only involved one participant, it is a compelling starting point for future research on a ketogenic diet combined with intermittent fasting. More research needs to be conducted on a combined IF and KD with strength training for optimal changes in body composition.
Introduction to Ketogenic Diet Combined with Intermittent Fasting
The ketogenic diet (KD) and intermittent fasting (IF) have gained significant attention in recent years for their potential benefits in weight loss, muscle mass gain, fat loss, and hormonal balance. A recent study titled “Keto Menu–Effect of Ketogenic Menu and Intermittent Fasting on the Biochemical Markers and Body Composition in a Physically Active Man—A Controlled Case Study” delves into the combined effects of ketogenic diet combined with intermittent fasting. This article aims to provide a comprehensive review of existing literature, focusing on the pros and cons of these dietary approaches.
Understanding Intermittent Fasting
IF involves cycling between periods of eating and fasting. The most popular forms include the 16/8 method, where you fast for 16 hours and eat within an 8-hour window, and the 5:2 method, where you consume a regular diet for five days and restrict calories for two non-consecutive days.
The Science Behind the Ketogenic Diet
The KD is a high-fat, low-carbohydrate diet that aims to shift your body’s metabolism from burning carbohydrates to burning fats for energy. This state is known as ketosis, achieved by consuming less than 50 grams of carbohydrates daily. The KD is unique in its approach to energy sourcing. Unlike other diets that rely on glucose, the KD puts the body into a state of nutritional ketosis, where ketone bodies become the primary energy source. (Puchalska & Crawford, 2017)
The diet often includes oily and lean fish, fatty and lean meats, eggs, seafood, dairy products, avocado, olives, and oils like olive and MCT oil. Low-glycemic fruits such as raspberries and blueberries are also included to a lesser extent. (Wilson & Lowery, 2017)
The Effectiveness of Keto Diet Meal Plan with Intermittent Fasting in Weight Loss
Both IF and KD have been found to be effective for weight loss. (Vargas-Molina et al., 2020; Welton et al., 2020) Most studies have found that when compared to a calorie-controlled diet, as long as protein intake is similar, both IF and KD result in similar weight loss as a reduced-calorie diet. (Kim, 2021; Moon & Koh, 2020)This suggests that the effectiveness of these diets may largely be attributed to their ability to help individuals control or reduce their overall caloric intake rather than any unique metabolic effects.
The principle of weight loss revolves around creating a calorie deficit, where the calories burned exceed the calories consumed. Both IF and KD can naturally lead to a reduction in calorie intake. IF does this by limiting the eating window, thus reducing opportunities for overeating, while KD does it by increasing satiety due to higher fat and protein consumption.
Given that the end goal is calorie control, the choice between IF, KD, and traditional calorie-restricted diets may come down to individual preferences and lifestyles. Some may find skipping meals with IF is easier, while others may find it more satisfying to eliminate certain macronutrients with a KD. For some, a ketogenic diet combined with intermittent fasting may be an alternative choice.
Muscle Mass and Keto Diet Plan with Intermittent Fasting
Traditionally, muscle mass gain has been associated with a high protein intake and a calorie surplus. Studies have shown that consuming more calories than you burn and adequate protein is essential for muscle growth. Most studies have found that both IF and KD diets are able to preserve muscle mass while dieting. (Moro et al., 2016; Patterson & Sears, 2017; Vargas et al., 2018; Wilson et al., 2020)
Both the ketogenic diet and intermittent fasting have their pros and cons. While they can be effective for weight loss, fat loss, and even increasing testosterone levels, they also have drawbacks. It’s essential to consult healthcare professionals before starting these diets, especially if you have existing health conditions.
The Role of Testosterone in Health
Testosterone, the primary male sex hormone, plays a crucial role in various physiological processes. While there are many ways to boost testosterone levels, two dietary approaches have garnered attention: the ketogenic diet and intermittent fasting benefits.
Persistent caloric deficits have been shown to reduce testosterone levels.(Cangemi et al., 2010) One study found that IF alone can also reduce testosterone concentration.(Cienfuegos et al., 2022) Studies regarding the KD effect on testosterone levels are mixed. A 2023 study showed a 74-97 ng/dL average increase in testosterone levels in 22 obese men following a ketogenic diet for 28 days.(Cignarelli et al., 2023) A 2022 meta-analysis suggested that a low-calorie ketogenic diet leads to a higher testosterone level increase than a normocaloric ketogenic diet.(Furini et al., 2023) However, this is not a universal finding, as some studies have shown a reduction in testosterone levels in men on a ketogenic diet. (Paoli et al., 2021)
Case Study of a Ketogenic Diet Combined with Intermittent Fasting
A new research case study documented the effects of a 13-week ketogenic diet combined with intermittent fasting (Delayed time-restricted eating 16:8 type) on testosterone levels, body composition, and other parameters in a healthy 23-year-old man performing strength training.
The man performed strength training 4-5 times a week. He took vitamin D3 and K2 supplements. Blood tests were conducted before and after the 13-week intervention to measure various biochemical parameters.
The ketogenic diet combined with intermittent fasting used a two-stage menu. The first stage was used for the first four weeks, and the second was used from week 5 to week 13. The two-stage dietary intervention resulted from the initial phase of body adaptation to using ketone bodies. Therefore, for the first four weeks (stage 1), a composition of macrocomponents was used to obtain optimal body adaptation to ketosis. After four weeks, the share of carbohydrates and protein increased, and the fat percentage was reduced. The caloricity at both stages of the intervention was identical (about 2450 kcal). In Stage 1, the diet consists of 100g of protein, 220g of fat, 20g of carbohydrates, and 17-22g of dietary fiber. In Stage 2, the protein intake increases to 136g, the fat intake decreases to 196g, and the carbohydrate intake increases to 33-37g. The dietary fiber remains the same at 20-26g.
Sample Stage 1 Diet: Ketogenic Diet Plan with Intermittent Fasting
Here is a sample menu of the ketogenic diet combined with intermittent fasting.
1st Meal (13:00): Chicken eggs, avocado, homemade mayonnaise, spinach leaves, tomato, linseed, gouda cheese, smoked sprats, extra butter, Himalayan salt, and still mineral water.
1st Meal (13:00): Pork shoulder, sour cream, onion, garlic, spinach leaves, extra butter, Himalayan salt, and still mineral water.
1st Meal (13:00): Chicken breast, sour cream, brussels sprouts, coconut oil, spinach leaves, red pepper, extra butter, and still mineral water.
1st Meal (13:00): Chicken eggs, smoked bacon, Brazil nuts, tomato, arugula, olive oil, gouda cheese, and still mineral water.
1st Meal (13:00): Chicken eggs, smoked sprats, arugula, homemade mayonnaise, pickled cucumbers, pumpkin seeds, olive oil, and still mineral water.
1st Meal (13:00): Pork knuckle, sauerkraut, broccoli, marinated boletes, extra butter, olive oil, and highly mineralized water.
1st Meal (13:00): Pork neck, Chinese cabbage, homemade mayonnaise, tomato, linseed, avocado, olive oil, and still mineral water.
Each day, there’s also a mention of black coffee brew (without sugar), MCT oil, and different types of water (still mineral water, highly mineralized water).
The first Meal was consumed at 13:00, followed by a second meal (primarily fat-based) at 17:00, and a third meal at 21:00. The participant typically slept around 24:00, ensuring a 3-hour gap between the last Meal and sleep.
Results and Findings
Over 13 weeks of using a ketogenic diet combined with intermittent fasting, the weight decreased by 10.9 kg or almost 24 pounds (12.6% reduction). Adipose tissue mass decreased by 6.5 kg or 14.3 pounds (43.9% reduction), while lean tissue mass increased. The body’s water increased, and there was a slight reduction in bone tissue mass. The body mass index (BMI) decreased by 3.3 kg/m2 (12.5% reduction).
Keto Diet Meal Plan with Intermittent Fasting Results
A muscle mass reduction of 4.1 kg or 9.02 pounds (from 68.4 kg to 64.3 kg/ 150.48 pounds to 141.4 pounds) corresponds to a 6% decrease. This reduction in muscle mass can be attributed to the fact that muscle mass consists of water and glycogen, which decrease while on a ketogenic diet, especially when combined with a caloric deficit. These results demonstrate the positive impact of the intervention on body composition.
The most intriguing study results were the testosterone responses. The study reported a significant increase in testosterone serum concentration. There increase was almost twofold, despite the already high values at baseline, reaching 172% above the laboratory limit of normal. Other positive findings included improved insulin sensitivity and lipid profile, increased HDL cholesterol, and decreased LDL cholesterol levels. (Dyńka et al., 2023)
Conclusion: Should You Intermittent Fast on Keto?
The synergistic effects of KD and IF, when combined with strength training, offer promising avenues for weight loss, muscle mass preservation, and hormonal balance. While the case study discussed is limited to a single individual, it is a compelling example of the transformative power of combining KD and IF with strength training.
Cangemi, R., Friedmann, A. J., Holloszy, J. O., & Fontana, L. (2010). Long-term effects of calorie restriction on serum sex-hormone concentrations in men. Aging Cell, 9(2), 236-242. https://doi.org/https://doi.org/10.1111/j.1474-9726.2010.00553.x
Cienfuegos, S., Corapi, S., Gabel, K., Ezpeleta, M., Kalam, F., Lin, S., Pavlou, V., & Varady, K. A. (2022). Effect of Intermittent Fasting on Reproductive Hormone Levels in Females and Males: A Review of Human Trials. Nutrients, 14(11).
Cignarelli, A., Santi, D., Genchi, V. A., Conte, E., Giordano, F., Di Leo, S., Natalicchio, A., Laviola, L., Giorgino, F., & Perrini, S. (2023). Very low-calorie ketogenic diet rapidly augments testosterone levels in non-diabetic obese subjects. Andrology, 11(2), 234-244. https://doi.org/https://doi.org/10.1111/andr.13357
Dyńka, D., Paziewska, A., & Kowalcze, K. (2023). Keto Menu–Effect of Ketogenic Menu and Intermittent Fasting on the Biochemical Markers and Body Composition in a Physically Active Man—A Controlled Case Study. Foods, 12(17).
Furini, C., Spaggiari, G., Simoni, M., Greco, C., & Santi, D. (2023). Ketogenic state improves testosterone serum levels—results from a systematic review and meta-analysis. Endocrine, 79(2), 273-282. https://doi.org/10.1007/s12020-022-03195-5
Kim, J. Y. (2021). Optimal Diet Strategies for Weight Loss and Weight Loss Maintenance. J Obes Metab Syndr, 30(1), 20-31. https://doi.org/10.7570/jomes20065
Moon, J., & Koh, G. (2020). Clinical Evidence and Mechanisms of High-Protein Diet-Induced Weight Loss. J Obes Metab Syndr, 29(3), 166-173. https://doi.org/10.7570/jomes20028
Moro, T., Tinsley, G., Bianco, A., Marcolin, G., Pacelli, Q. F., Battaglia, G., Palma, A., Gentil, P., Neri, M., & Paoli, A. (2016). Effects of eight weeks of time-restricted feeding (16/8) on basal metabolism, maximal strength, body composition, inflammation, and cardiovascular risk factors in resistance-trained males. J Transl Med, 14(1), 290. https://doi.org/10.1186/s12967-016-1044-0
Paoli, A., Cenci, L., Pompei, P., Sahin, N., Bianco, A., Neri, M., Caprio, M., & Moro, T. (2021). Effects of Two Months of Very Low Carbohydrate Ketogenic Diet on Body Composition, Muscle Strength, Muscle Area, and Blood Parameters in Competitive Natural Body Builders. Nutrients, 13(2).
Patterson, R. E., & Sears, D. D. (2017). Metabolic Effects of Intermittent Fasting. Annu Rev Nutr, 37, 371-393. https://doi.org/10.1146/annurev-nutr-071816-064634
Puchalska, P., & Crawford, P. A. (2017). Multi-dimensional Roles of Ketone Bodies in Fuel Metabolism, Signaling, and Therapeutics. Cell Metab, 25(2), 262-284. https://doi.org/10.1016/j.cmet.2016.12.022
Vargas, S., Romance, R., Petro, J. L., Bonilla, D. A., Galancho, I., Espinar, S., Kreider, R. B., & Benítez-Porres, J. (2018). Efficacy of ketogenic diet on body composition during resistance training in trained men: a randomized controlled trial. J Int Soc Sports Nutr, 15(1), 31. https://doi.org/10.1186/s12970-018-0236-9
Vargas-Molina, S., Petro, J. L., Romance, R., Kreider, R. B., Schoenfeld, B. J., Bonilla, D. A., & Benítez-Porres, J. (2020). Effects of a ketogenic diet on body composition and strength in trained women. Journal of the International Society of Sports Nutrition, 17(1), 19. https://doi.org/10.1186/s12970-020-00348-7
Welton, S., Minty, R., O’Driscoll, T., Willms, H., Poirier, D., Madden, S., & Kelly, L. (2020). Intermittent fasting and weight loss: Systematic review. Can Fam Physician, 66(2), 117-125.
Wilson, J., & Lowery, R. (2017). The ketogenic bible: The authoritative guide to ketosis. Simon and Schuster.
Wilson, J. M., Lowery, R. P., Roberts, M. D., Sharp, M. H., Joy, J. M., Shields, K. A., Partl, J. M., Volek, J. S., & D’Agostino, D. P. (2020). Effects of Ketogenic Dieting on Body Composition, Strength, Power, and Hormonal Profiles in Resistance Training Men. J Strength Cond Res, 34(12), 3463-3474. https://doi.org/10.1519/jsc.0000000000001935
Quick Facts: Intermittent Fasting and Keto
Intermittent fasting keto is a way of eating that combines periods of fasting with a high-fat diet. It offers numerous health benefits, including improved blood sugar control and insulin levels, reduced body fat, and enhanced brain function. This approach can help with medical conditions like epilepsy and Alzheimer’s disease.
It promotes autophagy and longevity, switches the fuel source from carbs to fats, and helps in blood pressure management. It’s effective for beginners but consult a healthcare provider if you have heart disease or insulin resistance.
Short periods of this diet can induce a metabolic switch, leading to a state of ketosis. This can aid in blood sugar levels regulation, reduce chronic inflammation, and improve mental clarity. Longer fasts and alternate-day fasting may also be beneficial.
For snacks, consider low-carb options like cauliflower. The diet naturally leads to consuming fewer calories, helping to manage body weight. It also boosts BDNF, a protein linked to physiology and mental health.
What is intermittent fasting and how does it complement the ketogenic diet?
Intermittent fasting is a pattern of eating that involves alternating periods of fasting and eating within a time frame. When combined with the ketogenic diet, intermittent fasting can enhance its benefits. Both approaches work synergistically to promote ketosis.