In recent times, the prevalence of obesity increases, reaching an epidemic scale. Elevated body weight is a risk factor in the development of several diseases such as diabetes, hypertension and cancer. Therefore, obesity management solutions, such as diet therapy are needed. The key issue is to choose the most appropriate diet to obtain an efficient outcome in losing weight, without experiencing adverse effects and a decrease in general health. A ketogenic diet, an auxiliary therapy for epilepsy, is recently one of the options commonly used for losing weight by overweight individuals, tempted by the commercials and internet influencers. However, there is limited knowledge about the effect of this diet on human health. To date, the majority of studies were conducted with a very-low-calorie regime applied before the bariatric surgeries, which itself may affect the loss of body weight, and in most studies, the control diets were missing. Taking into consideration that a ketogenic diet is an extremely eliminating diet, there is a risk of nutritional deficiencies after following it. Therefore, there is a strong need for more in-depth and comprehensive elucidation of the safety and physiological effects of the ketogenic diet used for the weight loss in overweight and obese individuals.

This Project aims to evaluate the effectiveness of the eight-week, isocaloric, energy-restricted, ketogenic diet as a weight management solution in women with overweight and obesity compared to the standard, balanced diet with the same calorie content.

In recent times, the prevalence of obesity increases, reaching an epidemic scale. A new factor supporting a weight gain is a current coronaviros (COVID-19) pandemic, associated with reduced physical activity, high stress and overeating, which resulted in 2-5 kg weight gain in 20 % of the American population within a few months 1. Elevated body weight is a risk factor in developing several diseases such as diabetes, hypertension and cancer. Therefore, obesity management solutions, such as diet therapy, are needed. The critical issue is to choose the most appropriate diet to obtain an efficient outcome in losing weight without experiencing adverse effects and a decrease in general health. A ketogenic diet, an auxiliary therapy for epilepsy, is recently one of the options commonly used for losing weight by individuals with overweight, tempted by the commercials and internet influencers. However, there is limited knowledge about the effect of this diet on human health. To date, the majority of studies were conducted with a very low-calorie regime applied before the bariatric surgeries, which itself may affect the loss of body weight. In most studies, the control diets were missing. Considering that a ketogenic diet is an extremely eliminating diet, there is a risk of nutritional deficiencies after following it. Therefore, there is a strong need for more in-depth and comprehensive elucidation of the safety and physiological effects of the energy-restricted ketogenic diet used for weight loss in individuals with overweight and obese.

This Project aims to evaluate the effectiveness of the eight-week, isocaloric, energy-restricted, ketogenic diet as a weight management solution in women with overweight and obesity compared to the standard, balanced diet with the same calorie content.

Inclusion Criteria:

• women
• age 18-45
• overweight (BMI 27 - 35)
• motivation to lose weight and participate in the nutritional intervention trial

Exclusion Criteria:

• overweight/obesity secondary to genetic syndromes
• endocrine diseases, acute systemic disease, autoimmune disorders
• pregnancy
• breastfeeding
• type 1 and 2 diabetes
• any other chronic diseases requiring pharmacotherapy (including topical steroids in allergy disorders
• supplement or medication use influencing appetite, weight or metabolism)
• participation in other clinical trials
• severe obesity (BMI > 35)
• > 3 kg weight loss 12 weeks before the initial test day
• extreme changes in exercise intensity 4 weeks prior
• any diagnosed psychiatric disorders

During the project only new data will be acquired and/or generated. No existing data re-usage is planned. Similar data do not exist yet, thus the planned project will be the only source/origin of them.

In the project the following data will be generated: numerical data, texts and graphical data (chromatography).

During the the project, two types of data will be generated to further processing:

1. automatic measurement data resulting from the equipment, obtained using the validated methodologies and calibrated equipments with the predefined replicates.
2. non-automatic measurement data resulting from carried out experiments - data documented manually and then entered into a spreadsheets and obtained after the statistical evaluation.

All data will be successfully published in prestigious journals with high Impact Factor. Thus, they will be evaluated by the expert reviewers in the process of revision.