The study:

In this study, the authors advanced that one of the key elements for a successful weight loss therapy in obese people depends on hunger and food control, as well as their psychological wellbeing. Therefore, the aim of this study was to evaluate the quality of life, food and alcohol cravings, physical and sexual activity, and sleep in obese individuals who followed a ketogenic diet, as well as the impact of ketosis and weight loss on these parameters.


The study was a cohort performed over the span of 4 months on patients attending the Obesity Unit at the Complejo Hospitalario Universitario of Santiago de Compostela (CHUS), Spain. The weight-loss program had five steps. The first three steps consist of a Very Low Calorie Ketogenic diet (600–800 kcal/day), being low in carbohydrates (<50 g daily from vegetables) and lipids (only 10 g of olive oil per day). The amount of proteins ranged between 0.8 and 1.2 g per each kg of ideal body weight to ensure that patients were meeting their minimum body requirements and to prevent the loss of lean mass. Throughout these ketogenic phases, supplements of vitamins and minerals, such as K, Na,Mg, Ca, and omega-3 fatty acids, were provided. These three steps were maintained until the patient lost the target amount of weight, ideally 80%. The total ketosis state lasted for 60–90 days only. In steps 4 or 5, the ketogenic phases were ended by the physician in charge of the patient based on the amount of weight lost, and the patient started a low-calorie diet (800–1500 kcal/day). The maintenance diet consisted of an eating plan balanced in carbohydrates, protein, and fat. Depending on the individual, the calories consumed ranged between 1500 and 2000 kcal/day.


The Very Low Calorie Ketogenic diet induced the expected weight loss, accompanied by significant improvements in psychological wellbeing (measured by quality of life scores, sexual function -for females-, physical activity and sleep quality.), and a decrease in food and alcohol cravings.


This work demonstrates that a Very Low Calorie Ketogenic diet induces a severe body weight reduction along with a decrease in food craving and improvements in psychological well-being measured by physical activity, sleep quality, female sexual function, and quality of life scores. In this study, normal side effects from low calorie diets of hunger, sadness, bad humor, and, in some cases, mild depression were absent in the patients following a Very Low Calorie Ketogenic diet, thus contributing to the success. Also, a reduction in food craving was observed despite the high-energy restriction. The study did not find significant changes in the sexual function of men during the nutritional intervention, although women reported that general sexual dysfunction improved, especially in the maximum ketosis phase. Importantly, in the current study, an improvement in the indexes of sleep was observed, especially at the point of maximum loss of fat mass. Overall, these psychobiological parameters were translated to an enhancement in general quality of life for the dieters.

Study editor:

Edgard Jr. El Sayegh holds a B.S in Medical Laboratory Sciences. He served as an Emergency Medical Tactician at the Lebanese Red Cross for three years and is now completing his M.D studies at the University Of Balamand, Beirut.


Castro, A., Gomez-Arbelaez, D., Crujeiras, A., Granero, R., Aguera, Z., Jimenez-Murcia, S., Casanueva, F. (2018). Effect of A Very Low-Calorie Ketogenic Diet on Food and Alcohol Cravings, Physical and Sexual Activity, Sleep Disturbances, and Quality of Life in Obese Patients. Nutrients, 10(10), 1348. doi:10.3390/nu10101348