Food is a necessity for peoples lives. Proper nutrition can improve peoples health and quality of life. As a national public nutritionist, I need to have a deep understanding of nutrition and health, and be able to provide professional and scientific nutrition guidance services to the public.In order to become a national public nutritionist, I need to pass the national public nutritionist level 4 examination. This examination requires a comprehensive understanding of nutrition, health and nutrition science. In order to pass the examination, I need to study and master the knowledge of human nutrition, nutrition requirements, nutrition-related diseases, nutrition assessment and nutrition counseling, food safety, and dietary planning and management.I need to understand the basic principles of human nutrition, such as the nutrient composition of food, the principles of nutrient metabolism, the physiological functions of nutrients, and the characteristics of nutrient requirements. At the same time, I need to master the knowledge of nutrition-related diseases, such as obesity, diabetes, hypertension, coronary heart disease, cancer and other chronic diseases. I also need to understand the principles and methods of nutrition assessment, as well as the principles and methods of nutrition counseling.In addition, I also need to master the relevant knowledge of food safety and dietary planning and management. Food safety is an important part of nutrition. I need to understand the sources of food risks, the methods of food safety control, and the principles of dietary planning and management.In order to meet the requirements of the national nutritionist level 4 examination, I need to systematically study nutrition, health and nutrition science. I need to focus on mastering the relevant knowledge of human nutrition, nutrition-related diseases, food safety and dietary planning and management. At the same time, I need to understand the principles and methods of nutrition assessment and nutrition counseling. With a comprehensive and in-depth understanding of nutrition and nutrition science, I believe I can pass the national nutritionist level 4 examination and become a professional national public nutritionist.