Ketone Ester Supplement Key Points:
- The study found that well-trained endurance athletes who consumed a ketone ester supplement before a 20-minute cycling time trial performed worse than those who consumed a placebo.
- The average 20-min time-trial power output was 2.4% lower after ketone ester supplement versus placebo ingestion.
- Based on the study, it appears that acute ketone monoester supplementation may impair endurance exercise performance in trained individuals. Therefore, it may not be advisable for athletes to take ketone supplements based on this study
Athletes are always in search of new methods to improve their performance. One such method is using ketone ester supplements, ketone salts (i,e., calcium, potassium, and magnesium ketone salts), and a low-carb, keto diet. Ketones are a natural byproduct of the body’s fat metabolism and are used for energy when glucose levels are low. The idea behind ketone ester supplements is to increase ketone levels to provide the body with an alternative source of energy that can enhance athletic performance.
Marketing and Use of Exogenous Ketone Bodies
Exogenous ketone bodies are marketed as a revolutionary carb alternative energy source to increase blood ketone levels, boost exercise performance and fat burning, cognition, and suppress appetite. Ketone esters are consumed in conjunction with caffeine by cyclists and runners worldwide to boost their performance, increase muscle recovery, and give an energy boost. However, recent research has raised questions about the efficacy of these supplements, with some studies suggesting that they may even hinder performance. (Margolis & O’Fallon, 2020; Quinones & Lemon, 2022)
The Debate Over Ketone Ester Supplements
However, there is a growing debate about whether these supplements do more harm than good. In this blog, we will delve into the science behind ketones and their role in energy production, explore what ketone ester supplements are and how they work, discuss the pros and cons of using them, and review recent studies that suggest they could be a performance inhibitor rather than an enhancer. Let’s navigate the controversy surrounding ketone esters and explore the future of research into this fascinating area.
Ketones: A Brief Overview of Ketosis and Nutrition
Ketones are molecules the liver produces during low carbohydrate intake or fasting periods. Ketone bodies, including acetoacetate, acetone, and β-hydroxybutyrate (BHB), are produced in the liver during periods of reduced carbohydrate availability and serve as an alternative fuel source for peripheral tissues, including the brain, heart, and skeletal muscle. (Evans et al., 2016)
The Impact of Nutritional Ketosis on Exercise
Nutritional ketosis induced through ingesting ketogenic supplements can alter physiological responses to exercise. This practice has also been purported to enhance performance under selected conditions. However, the precise mechanistic basis is unclear. The ketone monoester (KE) supplement has emerged as the preferred ketone body supplement because, for a given dose, it elicits a greater increase in blood ketone body concentrations and is generally well tolerated.
What is a Ketone Ester Supplement?
Ketone esters are a type of exogenous ketone, meaning they are ketones consumed in a supplement rather than produced by the body. They are often used by athletes as an alternative fuel source during exercise to enhance endurance and performance. The theory behind their use is that they can provide an efficient energy source for the body, particularly the brain, which can utilize ketones when glucose levels are low. Based on the review of the existing literature, the use of exogenous ketone esters in athletic performance presents both potential benefits and drawbacks.
Ketone Esters Benefits for Endurance Sports
The reported beneficial effects of ketone supplements are:
- Alternative Energy Source: Ketone esters are an alternative metabolic fuel source for ATP, reducing insulin levels, sparing carbohydrates, and potentially enhancing post-exercise glycogen replenishment. (Sansone et al., 2018)
- Reduced Protein Breakdown: They may reduce proteolysis, acting as metabolic modulators and signaling metabolites. (Chen et al., 2022)
- Improved Fuel and Muscle Efficiency: Some studies suggest improved fuel and muscle efficiency, with ketone drinks potentially decreasing lactate levels and sparing glycogen. (Dearlove et al., 2021)
- Weight Loss and Reduced Inflammation: Ketone esters (i.e., D-BHB ketones) are believed to aid in weight management by reducing the hunger hormone human ghrelin. They also can reduce inflammation.(Deemer et al., 2019; Soni et al., 2022)
- Improved Cognitive Function: Ketone ester supplementation may attenuate decrements in cognitive function during high-intensity exercise. (Quinones & Lemon, 2022)
- Potential Performance Improvement: Research suggests a potential 2 percent performance improvement for endurance athletes. (Quinones & Lemon, 2022)
CONS of Ketone Ester Drink
- Uncertain Efficacy: Conflicting evidence exists regarding the efficacy of exogenous ketones for endurance performance, necessitating further research for definitive conclusions.
- Potential Negative Effects: Potential negative effects include impaired sprint performance, gastrointestinal issues (i.e., nausea), and mild acidosis (i.e., ph disturbances). (POFFÉ et al., 2021)(EVANS & EGAN, 2018)
- Cost and Short-Term Effects: Ketone esters can be costly and have short-term effects. Limited research exists on their safety and long-term effects.
The Controversy Surrounding Ketone Esters: A Closer Look at the Research
Despite their popularity, the effectiveness of ketone esters as a performance-enhancing supplement is a topic of ongoing debate. While some studies have reported performance improvements following ketone ester supplementation, others have found no effect, and some have even reported a decline in performance.
It has been suggested that ketone esters may increase the capacity of muscles to oxidize fatty acids, leading to improved exercise capacity.(Nielsen et al., 2019) Additionally, ketone esters may alter fuel selection, mitochondrial bioenergetics, and intramuscular substrate utilization.(Egan & D’Agostino, 2016)
Ketones Supplements Research
The ingestion of ketogenic supplements can alter physiological responses to exercise and has been purported to enhance performance under selected conditions. However, the precise mechanistic basis is unclear. The effect of acute ketone monoester (KE) supplementation on endurance cycling performance in trained individuals has yielded equivocal data, which may be partly explained by between-study differences in any nutritional controls implemented, KE dosing, and exercise intensity.
A systematic review published in Advances in Nutrition analyzed the effects of ketone supplementation on physical performance. Out of the 16 performance outcomes evaluated in 10 studies involving 112 participants, 3 reported positive effects, 10 reported null effects, and 3 reported negative effects compared to controls. This heterogeneity among the studies makes it difficult to draw definitive conclusions. (Margolis & O’Fallon, 2020)
New Study of Ketone Esters
In a study published in the Journal of Human Kinetics, 10 participants consumed a ketone supplement or a placebo before a 5-kilometer running time trial. Despite increased ketones in the bloodstream, the results showed no significant improvement in performance or other measured variables. (Prins et al., 2020)
On the other hand, a study published in Nutrients examined the effects of ketone supplementation on cognitive performance during a simulated soccer match. The study found that ketone monoester supplementation reduced blood glucose and lactate concentrations during the match and attenuated the decline in cognitive performance compared to the placebo. (Quinones & Lemon, 2022)
However, a study published in Medicine and Science in Sports and Exercise investigated the effects of a similar calories diet of ketogenic low-carbohydrate, high-fat (LCHF) diet and ketone ester (KE) supplementation on exercise metabolism and performance in elite race walkers. The results showed that the LCHF diet increased fat oxidation but impaired exercise economy and race performance. KE supplementation did not improve exercise metabolism or performance. (Whitfield et al., 2021)
New Ketone Ester Study Finds Decreased Athletic Performance.
A recent study published in the International Journal of Sports Nutrition and Exercise Metabolism has added to this controversy. To be eligible for the study, researchers included healthy adults aged between 18 and 60 years, consuming>50 g/day of carbohydrates, that is, not following a ketogenic diet. Participants were instructed to maintain their usual dietary and exercise habits throughout the study. The subject had experience in competitive cycling, time trials, or racing, habitually engaging in≥5 hr./week of cycling training over≥3 days/week, and had a high aerobic capacity.
The experimental interventions were acute ingestion of either 0.35 g/kg body mass of a KE or a ketone-free placebo 30 min before exercise. Participants were instructed to maintain their usual dietary and exercise habits throughout the study and to eat and drink how they normally prepare for a race the day before and the morning of the trials.
The study found that well-trained endurance athletes who consumed a ketone supplement before a 20-minute cycling time trial performed worse than those who consumed a placebo. The average 20-min time-trial power output was 2.4% lower after KE versus PL ingestion. The ingestion of the ketone esters lowered blood glucose levels, which could have impacted performance. Participants felt more exertion or effort during exercise after ingesting the ketone esters compared to the placebo. The study’s authors suggested that this decrease in performance may relate to the effect of ketone ester ingestion on blood acid–base status, heart rate, and/or perceived exertion. However, the mechanistic basis for impaired athletic performance after ketone ingestion under the present study conditions remains to be determined.
The Future of Ketone Ester Research
Ongoing studies are exploring the potential benefits of ketone ester supplements beyond sports. Ketone esters have applications in medical treatments for conditions like epilepsy and Alzheimer’s disease. Ethical considerations require regulations to ensure fairness in sports.
Future studies should consider factors such as the type of ketone ester used, βHB concentrations, palatability, substrate metabolism, and gastrointestinal distress, which may contribute to inconsistent outcomes.
To sum up, while ketone ester supplements can improve physical and cognitive performance, it’s crucial to weigh the pros against the cons. Adequate dosage, timing, and duration of supplementation should be emphasized for optimal outcomes.
Chen, J., Li, Z., Zhang, Y., Zhang, X., Zhang, S., Liu, Z., Yuan, H., Pang, X., Liu, Y., Tao, W., Chen, X., Zhang, P., & Chen, G.-Q. (2022). Mechanism of reduced muscle atrophy via ketone body (D)-3-hydroxybutyrate. Cell & Bioscience, 12(1), 94. https://doi.org/10.1186/s13578-022-00826-2
Dearlove, D. J., Harrison, O. K., Hodson, L., Jefferson, A., Clarke, K., & Cox, P. J. (2021). The Effect of Blood Ketone Concentration and Exercise Intensity on Exogenous Ketone Oxidation Rates in Athletes. Med Sci Sports Exerc, 53(3), 505-516. https://doi.org/10.1249/mss.0000000000002502
Deemer, S. E., Davis, R. A. H., Gower, B. A., Koutnik, A. P., Poff, A. M., Dickinson, S. L., Allison, D. B., D’Agostino, D. P., & Plaisance, E. P. (2019). Concentration-Dependent Effects of a Dietary Ketone Ester on Components of Energy Balance in Mice. Front Nutr, 6, 56. https://doi.org/10.3389/fnut.2019.00056
Egan, B., & D’Agostino, D. P. (2016). Fueling Performance: Ketones Enter the Mix. Cell Metabolism. https://doi.org/10.1016/j.cmet.2016.08.021
EVANS, M., & EGAN, B. (2018). Intermittent Running and Cognitive Performance after Ketone Ester Ingestion. Medicine & Science in Sports & Exercise, 50(11), 2330-2338. https://doi.org/10.1249/mss.0000000000001700
Evans, M. I., Cogan, K. E., & Egan, B. (2016). Metabolism of Ketone Bodies During Exercise and Training: Physiological Basis for Exogenous Supplementation. The Journal of Physiology. https://doi.org/10.1113/jp273185
Margolis, L. M., & O’Fallon, K. S. (2020). Utility of Ketone Supplementation to Enhance Physical Performance: A Systematic Review. Adv Nutr, 11(2), 412-419. https://doi.org/10.1093/advances/nmz104
Nielsen, R., Møller, N., Gormsen, L. C., Tolbod, L. P., Hansson, N. H., Sørensen, J. N., Harms, H. J., Frøkiær, J., Eiskjær, H., Jespersen, N. R., Mellemkjær, S., Lassen, T. R., Pryds, K., Bøtker, H. E., & Wiggers, H. (2019). Cardiovascular Effects of Treatment With the Ketone Body 3-Hydroxybutyrate in Chronic Heart Failure Patients. Circulation. https://doi.org/10.1161/circulationaha.118.036459
POFFÉ, C., WYNS, F., RAMAEKERS, M., & HESPEL, P. (2021). Exogenous Ketosis Impairs 30-min Time-Trial Performance Independent of Bicarbonate Supplementation. Medicine & Science in Sports & Exercise, 53(5), 1068-1078. https://doi.org/10.1249/mss.0000000000002552
Prins, P. J., Koutnik, A. P., D’Agostino, D. P., Rogers, C. Q., Seibert, J. F., Breckenridge, J. A., Jackson, D. S., Ryan, E. J., Buxton, J. D., & Ault, D. L. (2020). Effects of an Exogenous Ketone Supplement on Five-Kilometer Running Performance. J Hum Kinet, 72, 115-127. https://doi.org/10.2478/hukin-2019-0114
Quinones, M. D., & Lemon, P. W. R. (2022). Ketone Ester Supplementation Improves Some Aspects of Cognitive Function during a Simulated Soccer Match after Induced Mental Fatigue. Nutrients, 14(20). https://doi.org/10.3390/nu14204376
Sansone, M., Sansone, A., Borrione, P., Romanelli, F., Di Luigi, L., & Sgrò, P. (2018). Effects of Ketone Bodies on Endurance Exercise. Curr Sports Med Rep, 17(12), 444-453. https://doi.org/10.1249/jsr.0000000000000542
Soni, S., Martens, M. D., Takahara, S., Silver, H. L., Maayah, Z. H., Ussher, J. R., Ferdaoussi, M., & Dyck, J. R. B. (2022). Exogenous ketone ester administration attenuates systemic inflammation and reduces organ damage in a lipopolysaccharide model of sepsis. Biochim Biophys Acta Mol Basis Dis, 1868(11), 166507. https://doi.org/10.1016/j.bbadis.2022.166507
Whitfield, J., Burke, L. M., McKay, A. K. A., Heikura, I. A., Hall, R., Fensham, N., & Sharma, A. P. (2021). Acute Ketogenic Diet and Ketone Ester Supplementation Impairs Race Walk Performance. Med Sci Sports Exerc, 53(4), 776-784. https://doi.org/10.1249/mss.0000000000002517
Is there any side effects to using a ketone ester supplement?
Some studies suggest that high doses of ketone ester supplements may cause digestive discomfort, including nausea, diarrhea, and stomach pain. However, more research is needed to determine the long-term side effects of using ketone ester supplements.