A high protein diet was superior to ketone esters for preserving muscle mass while dieting. High protein and ketone esters preserved aerobic capacity while dieting. Ketone esters were superior to high protein for preserving metabolic rate while dieting. The Ketone ester group had lower stress parameters compared to the other groups. Combining exogenous ketones and high protein may be advantageous while dieting. Contrary to other studies, the high protein group did not reduce appetite.


KETONE ESTERS VS HIGH PROTEIN ENERGY-RESTRICTED DIET SUMMARY

  • A high protein diet was superior to ketone esters for preserving muscle mass while dieting.

  • High protein and ketone esters preserved aerobic capacity while dieting.

  • Ketone esters were superior to high protein for preserving metabolic rate while dieting.

  • The Ketone ester group had lower stress parameters compared to the other groups.

  • Combining exogenous ketones and high protein may be advantageous while dieting.

  • Contrary to other studies, the high protein group did not reduce appetite.


Introduction to Ketone Esters

Maintaining lean body mass while reducing body fat percentage is important for any bodybuilder or athlete while dieting. Numbers on the scale don’t mean much if you have lost muscle and have reduced athletic performance. The negative effects of food restriction and reduced calorie intake while dieting includes:

1. Reduced resting metabolic rate

2. Loss of lean muscle mass

3. Increased hunger

4. Reduced exercise performance.

Dieting for prolonged periods can result in metabolic adaptation.  Metabolic adaptations to calorie restriction results in fewer calories burned per day.  Long-term dieting can result in losing body fat and muscle at a 3:1 ratio. (Weinheimer et al., 2010)

While dieting, it is not uncommon to feel sluggish and lethargic. This decrease in energy causes a reduction in daily physical activity resulting in a decrease in total daily energy expenditure. Generally, when on a diet, people may go to the gym. However, other activities may be reduced, such as spending more time sitting down and less time walking around.

Maintaining Muscle Mass While Dieting

Strength training is essential for maintaining muscle mass. A reduced number of calories can result in decreased muscle protein synthesis and an increase in muscle tissue breakdown. (Carbone et al., 2013; Pasiakos et al., 2010) A high-protein diet has been shown to preserve muscle mass while dieting. (Tinsley et al., 2019)

Ketogenic diets can raise blood ketone levels, but ketone supplements such as ketone esters can also increase blood ketone levels. Exogenous ketone esters can reduce muscle tissue breakdown and stimulate anabolic activity in muscles by stimulating mTOR. (Nair et al., 1988; Vandoorne et al., 2017)

Both high protein and ketone esters show anabolic and anti-catabolic properties. In a remarkable study, scientists from France examined the effects of a high-protein diet and a ketone ester supplement on the maintenance of muscle mass and performance in young women on a diet.

vo2máx ketone ester vo2max test signs of losing muscle mass resting metabolic rate test food restriction resting metabolic rate is exogenous ketone esters ketosis vs calorie restriction metabolic adaptation to calorie restriction energy restricted di

A high-protein diet has been shown to preserve muscle mass while dieting. (Tinsley et al., 2019)

HIGH PROTEIN VS KETONE ESTERS: WHICH IS BETTER FOR REDUCING MUSCLE LOSS

Young females were assigned to a 30% calorie-restricted diet but were assigned to three groups. All groups were instructed to maintain their normal physical activity and exercise program. The three groups were:

·      Calorie-restricted diet and high protein and a placebo (i.e., 2-2.2 g/kg/day .9-1 gram per pound of body weight)

·      Calorie-restricted diet plus exogenous ketone ester drink and low protein (20 grams of ketone esters 3 times per day).  Protein intake was set at .8-1.0 g/kg/day or .4-.5 grams of protein per day)

·      Placebo group: Low protein and a placebo Protein intake was set at .8-1.0 g/kg/day or .4-.5 grams of protein per day)

So why did the ketone ester group receive low protein? The researchers wanted to test if ketone esters are truly anti-catabolic.  The best way to have a person lose muscle is to place them on a low-protein diet while dieting. Previous research has shown that ketones are anti-catabolic when subjects are eating adequate calories. Therefore, this study wanted to test the responses to a calorie-restricted diet.

The researchers tracked body composition (i.e., signs of losing muscle mass), performed resting metabolic rate tests, took blood samples, and tested aerobic capacity (i.e., vo2máx).  A VO2max test is a maximal aerobic capacity test in which you run or bike until complete exercise exhaustion to test aerobic capacity.

RESTING METABOLIC RATE RMR TESTING

Resting metabolic rate is a measure of how many calories you are burning at rest. A DEXA is a body composition analyzer that measures bone mass, lean muscle mass, and % body fat.

Maintaining muscle mass is important for preserving metabolic rate. (Ravussin et al., 1986) If muscle mass is decreased with dieting, weight loss is harder because your body is burning fewer calories.

KETOSIS VS CALORIE RESTRICTION WITH HIGH PROTEIN

At the end of the 4-week study, only the high protein diet inhibited muscle tissue breakdown in the dieting females. The high protein diet also maintained aerobic capacity compared to the control group. Despite the preserved muscle mass, this did not prevent a decline in metabolic rate.  The exogenous ketone esters did not preserve muscle mass, but supplementation did have positive effects.

vo2máx ketone ester vo2max test signs of losing muscle mass resting metabolic rate test food restriction resting metabolic rate is exogenous ketone esters ketosis vs calorie restriction metabolic adaptation to calorie restriction energy restricted di

Only the ketone ester supplementation group preserved resting metabolic rate and physical activity energy expenditure (PAEE). PAEE measures how many calories you burn outside the gym thru normal daily activities (i.e., walking, standing, etc.).  This means that ketone-ester groups preserved their daily activities during the day.

The ketone ester group preserved aerobic capacity to the same capacity as the high protein group. Additionally, the ketone ester group had lower stress parameters than the other groups.

Contrary to many studies, the high protein group did not have a reduction in appetite.  Neither ketone esters nor high protein affected appetite regulation.(Hiroux et al., 2023)

This study suggests that protein is the king of preserving muscle mass while dieting. However, combining ketone esters and high protein may be a good combination. Only the ketone ester supplement group could preserve metabolic rate. They also had a lower stress rating. Future research should test high-protein diets combined with ketone esters to examine these effects.

REFERENCES

Carbone, J. W., Margolis, L. M., McClung, J. P., Cao, J. J., Murphy, N. E., Sauter, E. R., Combs Jr., G. F., Young, A. J., & Pasiakos, S. M. (2013). Effects of energy deficit, dietary protein, and feeding on intracellular regulators of skeletal muscle proteolysis. The FASEB Journal, 27(12), 5104-5111. https://doi.org/https://doi.org/10.1096/fj.13-239228

Hiroux, C., Schouten, M., de Glisezinski, I., Simon, C., Crampes, F., Hespel, P., & Koppo, K. (2023). Effect of increased protein intake and exogenous ketosis on body composition, energy expenditure, and exercise capacity during a hypocaloric diet in recreational female athletes [Original Research]. Frontiers in Physiology, 13. https://doi.org/10.3389/fphys.2022.1063956

Nair, K. S., Welle, S. L., Halliday, D., & Campbell, R. G. (1988). Effect of beta-hydroxybutyrate on whole-body leucine kinetics and fractional mixed skeletal muscle protein synthesis in humans. The Journal of clinical investigation, 82(1), 198-205. https://doi.org/10.1172/JCI113570

REFERENCES

Pasiakos, S. M., Vislocky, L. M., Carbone, J. W., Altieri, N., Konopelski, K., Freake, H. C., Anderson, J. M., Ferrando, A. A., Wolfe, R. R., & Rodriguez, N. R. (2010). Acute Energy Deprivation Affects Skeletal Muscle Protein Synthesis and Associated Intracellular Signaling Proteins in Physically Active Adults1,2. The Journal of Nutrition, 140(4), 745-751. https://doi.org/https://doi.org/10.3945/jn.109.118372

Ravussin, E., Lillioja, S., Anderson, T. E., Christin, L., & Bogardus, C. (1986). Determinants of 24-hour energy expenditure in man. Methods and results using a respiratory chamber. The Journal of clinical investigation, 78(6), 1568-1578. https://doi.org/10.1172/JCI112749

Tinsley, G. M., Trexler, E. T., Smith-Ryan, A. E., Paoli, A., Graybeal, A. J., Campbell, B. I., & Schoenfeld, B. J. (2019). Changes in Body Composition and Neuromuscular Performance Through Preparation, 2 Competitions, and a Recovery Period in an Experienced Female Physique Athlete. The Journal of Strength & Conditioning Research, 33(7), 1823-1839. https://doi.org/10.1519/jsc.0000000000002758

Vandoorne, T., De Smet, S., Ramaekers, M., Van Thienen, R., De Bock, K., Clarke, K., & Hespel, P. (2017). Intake of a Ketone Ester Drink during Recovery from Exercise Promotes mTORC1 Signaling but Not Glycogen Resynthesis in Human Muscle [Original Research]. Frontiers in Physiology, 8. https://doi.org/10.3389/fphys.2017.00310

Weinheimer, E. M., Sands, L. P., & Campbell, W. W. (2010). A systematic review of the separate and combined effects of energy restriction and exercise on fat-free mass in middle-aged and older adults: implications for sarcopenic obesity. Nutrition Reviews, 68(7), 375-388. https://doi.org/10.1111/j.1753-4887.2010.00298.x

About The Author

%d