In the world of today, each and every day there is a new diet being promoted by opinion leaders, who are »convinced« that the diet they are supporting is the best. I put the word convinced in quotation marks because it is not always the case that they actually believe their diet is superior to others, they just appear to believe to appeal more to general public i.e their fans for their own benefits. Ketogenic diet is a term that appeared around 100 years ago (Masood, 2018), but we can say that the popularity of this term has increased greatly in the past few years. Seeing as I am only interested in the effects of ketogenic diet on the weight, I will disregard the other effects it has on the body in this article. To explain, I will focus only on the question »is the ketogenic diet suitable for weight loss?«. There are many researches reporting about the effects of ketogenic diet and for that reason I will only include the latest of research. And for those reading, who have never heard of the ketogenic diet, it is a diet extremely high in fat, moderate in protein and extremely low in carbohydrates. To be exact, the ketogenic diet consists of around 55-60% fat, 30-35% protein and 5-10% carbohydrates (Masood, 2018).
Research shows, that the ketogenic diet is a suitable diet for weight loss, but we have to mention the fact that the weight one loses may not be quality weight loss, meaning fat loss (Kosinski, 2017). A study, where a group of mice were fed with a ketogenic diet for 12 weeks and the other group were fed with a mice food diet, has shown that the mice fed with a ketogenic diet ended up with a higher body fat percent than regular mice (Garbow et al v Kosinski, 2017). Another study has shown that a group of mice, which were fed with a ketogenic diet for 80 weeks, has been losing weight consistently in the first weeks, but after 18 weeks they started to gain weight. The reason for the weight loss is in the increase of energy expenditure, that »keto« mice were experiencing. It also has to be mentioned that a ketogenic diet intented for mice, is different than those intented for humans (Kosinski, 2017). Meaning we can't generalize the findings on mice to humans, we can use them as guidelines though.
As it was mentioned previously, there was an increase in energy expenditure on mice which were fed a ketogenic diet, and a study carried out by Hall confirms that there is a relatively small increase in energy expenditure (Hall, 2016). In another study, where the participants were 24 healthy males from the ages of 25 to 35, it has been shown that at the end of the diet they had less muscle mass in comparison to the start, while the group of »non-ketogenic« males and the control group actually gained muscle mass. It is worth mentioning that the »ketogenic« group lost the most body fat (Vargas, 2018). We can conclude, considering the studies stated above, that the ketogenic diet is more succesful for losing body fat than a non-ketogenic diet and the diet consumed by the control group. For comparison, the group that was following a ketogenic diet lost approximately twice more body fat than the group that was following a non-ketogenic diet. It has to be said, that the »ketogenic« group has lost muscle mass, while the »non-ketogenic« group has gained muscle mass (Vargas, 2018). Again, we can generalize that the ketogenic diet is more succesful in losing fat than the non-ketogenic diet, but in the long run it is the non-ketogenic diet that has the edge, because the non-ketogenic diet is more friendly to mantaining muscle mass. In support to that statement Hall summarizes that with ketogenic diet pace of losing body fat slows down with time (Hall, 2016).
To conclude, the ketogenic diet is a succesful diet for losing weight. It is not a succesful diet for mantaining muscle mass in the process of losing weight. So if the individual is not bothered by loss of muscle-mass ketogenic diet is the way to go.
Source:
Masood, W in Uppaluri KR. 2018. Ketogenic Diet. Accessed from: https://www.ncbi.nlm.nih.gov/books/NBK499830/?report=reader (25.1.2019)
Kosinski, C. In Jornayvaz FR. 2017. Effects of Ketogenic Diets on Cardiovascular Risk Factors: Evidence from Animal and Human Studies. Nutrients. 9 (5), 1-16. Accessed from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5452247/pdf/nutrients-09-00517.pdf (25.1.2019)
Vargas, S. 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). Accessed from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6038311/pdf/12970_2018_Article_236.pdf (25.1.2019).
Hall, K. D. 2016. Energy expenditure and body composition changes after an isocaloric ketogenic diet in overweight and obese men. The American journal of clinical nutrition. 104 (2), 324-333. Accessed from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4962163/pdf/ajcn133561.pdf