The purpose of writing this paper is to investigate differences in the level of nutrition conditioned by gender predispositions on a sample of a certain number of preschool children, of course, if they really do exist. The research is conducted in order to familiarize the general public with the problems of malnutrition and obesity, with which a large part of the community may not be familiar. It is important to note that the preschool age is particularly important for a child's development, so it is therefore crucial to provide the child with a healthy and balanced diet that does not lean towards unhealthy sides on the spectrum of types of nutrition. Since malnutrition and obesity in children, respectively, is an increasingly common phenomenon in today's society and lifestyle, this work aims to investigate whether there is a difference in the mentioned extreme conditions in male and female children, or whether these phenomena are gender-based. This paper will show whether these phenomena are real or unfounded speculations. If the results of the research show that there really are gender differences in malnutrition, that is, obesity in children, it is necessary to react urgently in accordance with these results. Ultimately, the results of this work will suggest how to proceed in the education and creation of the healthiest possible diet and lifestyle for children in order to ensure a healthier and more pleasant life for them in their coming years.