【Medical Q&A】What exactly are nutrients?

Planner: Chinese Medical Association

Reviewer: Gong Weiyan, Associate Researcher, Institute of Nutrition and Health, Chinese Center for Disease Control and Prevention

People often mention the word "nutrients" in daily life. We all know that nutrients are a type of substance necessary to maintain life and health, but in fact many people do not understand what nutrients are.

Nutrients are substances that need to be taken from the external environment to maintain all life activities and processes such as reproduction, growth, development and survival of the body. The discovery of nutrients is a great contribution of scientists to mankind. At present, there are more than 40 known nutrients, which can be divided into seven categories: protein, lipids, carbohydrates, vitamins, minerals, water, and dietary fiber. Among them, the requirements of protein, lipids and carbohydrates (these three types of nutrients can provide energy for the human body, also known as "energy-producing nutrients") are relatively large, called "macronutrients", and the requirements of vitamins and minerals are relatively small, called "micronutrients". Vitamins include water-soluble vitamins (including B vitamins and vitamin C) and fat-soluble vitamins (including vitamin A, vitamin D, vitamin E, vitamin K); minerals include macroelements (the content in the human body exceeds 0.01% of body weight, including calcium, phosphorus, potassium, sodium, magnesium, sulfur, and chlorine) and trace elements (the content in the human body is less than 0.01% of body weight, including iron, zinc, selenium, iodine, fluorine, copper, molybdenum, manganese, chromium, nickel, vanadium, tin, silicon, and cobalt 14). By eating a balanced diet, you can ensure that the human body takes in enough nutrients to maintain good health and prevent diseases.