Introduction: Obesity constitutes the base of numerous important problems on young people’sphysical and mental health, having its roots in childhood. Its prevalence remains in high levels both in developed and developing countries. The current way of life plays the basic role in its occurrence and affects children’s dietary patterns and their food choices. The bad eating habits and the increasing intake of calories may have harmful consequences on their health, especially when they take place during infancy and childhood. A child’s growing may be affected by the environment in which it is raised, while its dietary exposure to toxic and non-toxic metals, can reduce the intake of nutritional substances and disrupt the human’s body balance.Purpose: The aim of this thesis was to investigate the influence of eating habits resulting in theappearance of obesity during infancy. An additional aim was the evaluation of overweight and obese children, as well as, the study on children’s lifestyle which may contribute to the appearance of being overweight and obese. Also, the purpose of this thesis was the investigation of metal’s concentration in a child’s body and its influence on a child’s weight.Materials – Methods: The sample include 178 infants. The information was gathered byquestionnaires completed by parents and children’s educators, through which demographic andanthropometric data was evaluated, but also the eating and mealtime habits both of children and their families. The influence of nutritional factors on children’s BMI was also studied as well as their parent’s perception on their diet and weight. Moreover, samples of children’s hair, were collected, which were analyzed in order to study the concentration of metals in their body, and its influence on their health and weight.Results: On the whole, 20,37% and 3,7% of the children in this study, were overweight and obeserespectively. The children who had an increasing body weight from the first year of their life tended to maintain it at high levels, in the following years. The factors which seemed to affect the possibility of being obese and overweight, were the consumption of meals at fast food restaurants, the consumption of food while watching TV and the lack of physical exercise. It was concluded that parents had a misconception about their children’s body weight and eating habits. The majority of the children displayed a lack of zinc and copper, while the rest of the metals were detected in normal amounts.There was no relevance between children’s BMI and metal’s rate.Conclusions: It was concluded that the some eating habits may affects children’s weight increase.Furthermore, parent’s misconception about their children’s diet and weight constitutes a preventivefactor for the prevention and cure of the obese and overweight.