Proper nutrition is key to maintaining a healthy body. Proper nutrition strengthens the ability to counteract infections. However, many individuals give up healthy eating for a variety of reasons, including lack of knowledge, a busy schedule, and exhaustion. Proper nutrition is of utmost importance, especially in childhood, when proper growth and development of the body is crucial. The purpose of writing this final paper is to state all the essential facts concerning healthy eating. This paper consists of eight chapters and emphasizes the key role that food plays for human health. The reasons for a healthy diet are emphasized, and in the first part of the paper, all nutritional aspects of the diet are more closely covered, with proteins, carbohydrates, healthy fats, vitamins and minerals particularly prominent. Further research gives an insight into the proper nutrition of children from the very beginning, i.e. from conception. It also states the importance of proper nutrition both in infancy and preschool, and cites the pyramid of proper nutrition, which was made as a guideline of what we should consume. Then the impact of improper nutrition and its disorders is processed. In this section we list possible allergies, constipation, chronic diarrhea, obesity and malnutrition, as well as the impact of white sugar and processed foods on the human body. In conclusion, obesity and poor diet pose serious health challenges. Unhealthy diet, plenty of sugar and fat, contributes to excess body mass and increases the risk of diabetes, heart disease and other problems. Knowledge and awareness of the importance of a healthy diet are necessary to prevent obesity and preserve health. Promoting a balanced diet rich in a variety of foods is of great importance for preventing the negative consequences of poor nutrition.