Is the Keto Diet Actually Harming Your Fitness?
The popular notion that carbs are the enemy of weight loss has given rise to low carb diets all over the world. Of these, comes the ketogenic diet, a diet similar to the Atkin’s diet, sharing the same principle of consuming foods high in fat and receding intake of carbs to minuscule levels.
The keto diet aims to induce a state of ketosis in order to shed fat and improve metabolic functions, including athletic performance. But could the diet actually be harming your fitness?
Ketosis has been shown to undermine fitness in non-athletes. The diet is linked to increased fatigue, mood disturbances and perceived effort during exercise, suggesting the desire to adhere to exercise programs may actually decline in individuals trying to lose weight.
For endurance athletes, the keto diet has been associated with the shrinkage of muscle mass and a blunt in both aerobic and anaerobic performance.
A study conducted on participants enrolled in an eight-week exercise program compromised of strength exercises targeting the entire body, including bench presses, squats and deadlifts found no increase in muscle mass in those on a ketogenic diet, while individuals not on a keto diet had a significant boost in muscle. An average loss of 3.5 ounces of muscle was observed in those in the keto group, while those in the non-keto group put on an average of 1.3kg of muscle in just eight weeks.
Bone density is also affected on a keto diet. The diet is known to lead to a chronic acidotic state since ketones are acidic. This leads to an increased risk of bone fractures, stunted growth and bone loss.
So who can benefit from a keto diet?
Keto diets may help those with a rare genetic disorder called ‘glucose transporter deficiency syndrome’, in which blood sugar is unable to reach the brain. Secondly, epilepsy sufferers who don’t respond to anti-convulsion drugs may benefit from a keto diet.
If you’re considering adopting a keto diet for weight loss and physical performance, I would strongly advise against it. But as with anything, do your own research and decide what is right for you.
For more tips on all things health and wellness, subscribe to my newsletter. You’ll be the first to know about new articles and healthy recipes to support you on your wellness journey.
References
Aragon, A. A., Schoenfeld, B. J., Wildman, R., Kleiner, S., VanDusseldorp, T., Taylor, L., Earnest, C. P., Arciero, P. J., Wilborn, C., Kalman, D. S., Stout, J. R., Willoughby, D. S., Campbell, B., Arent, S. M., Bannock, L., Smith-Ryan, A. E., & Antonio, J. (2017). International society of sports nutrition position stand: diets and body composition. Journal of the International Society of Sports Nutrition, 14, 16. https://doi.org/10.1186/s12970-017-0174-y
Burke, L. M., Ross, M. L., Garvican-Lewis, L. A., Welvaert, M., Heikura, I. A., Forbes, S. G., Mirtschin, J. G., Cato, L. E., Strobel, N., Sharma, A. P., & Hawley, J. A. (2017). Low carbohydrate, high fat diet impairs exercise economy and negates the performance benefit from intensified training in elite race walkers. The Journal of physiology, 595(9), 2785–2807. https://doi.org/10.1113/JP273230
Groesbeck, D. K., Bluml, R. M., & Kossoff, E. H. (2006). Long-term use of the ketogenic diet in the treatment of epilepsy. Developmental medicine and child neurology, 48(12), 978–981. https://doi.org/10.1017/S0012162206002143
Kephart, W. C., Pledge, C. D., Roberson, P. A., Mumford, P. W., Romero, M. A., Mobley, C. B., Martin, J. S., Young, K. C., Lowery, R. P., Wilson, J. M., Huggins, K. W., & Roberts, M. D. (2018). The Three-Month Effects of a Ketogenic Diet on Body Composition, Blood Parameters, and Performance Metrics in CrossFit Trainees: A Pilot Study. Sports (Basel, Switzerland), 6(1), 1. https://doi.org/10.3390/sports6010001
Simm, P. J., Bicknell-Royle, J., Lawrie, J., Nation, J., Draffin, K., Stewart, K. G., Cameron, F. J., Scheffer, I. E., & Mackay, M. T. (2017). The effect of the ketogenic diet on the developing skeleton. Epilepsy research, 136, 62–66. https://doi.org/10.1016/j.eplepsyres.2017.07.014
White, A. M., Johnston, C. S., Swan, P. D., Tjonn, S. L., & Sears, B. (2007). Blood ketones are directly related to fatigue and perceived effort during exercise in overweight adults adhering to low-carbohydrate diets for weight loss: a pilot study. Journal of the American Dietetic Association, 107(10), 1792–1796. https://doi.org/10.1016/j.jada.2007.07.009
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. Journal of the International Society of Sports Nutrition, 15(1), 31. https://doi.org/10.1186/s12970-018-0236-9
