What nutrients do we need?

Nutrients: Substances that humans must ingest in order to maintain normal physiological functions and life needs. They are the material basis for ensuring human health. This article introduces: What nutrients do we need?

Let's first look at the composition of the human body. At the molecular level, there are six types of chemical substances that make up the human body: water, protein, fat, carbohydrates, minerals, and vitamins.

water

Water accounts for about 50% to 70% of the human body. Water accounts for the majority. Did you expect that? Although water is cheap, we cannot live without it.

I will not introduce the issue of water in detail in the future, so I will say a few more words in this article.

50%～70%, why is the difference so big?

People vary greatly in their fatness and thinness. Fat people have more fat, and fat contains less water, so the water ratio is lower. Thin people have less fat and more muscle, and muscle contains more water, so the water ratio is higher.

What is the function of water? Is it necessary to drink it?

The main physiological functions of water are: forming cell tissues, participating in material metabolism, promoting biochemical reactions, maintaining body fluid balance, regulating body temperature, and lubricating to reduce wear. Without water, we cannot live without it!

It is recommended to drink boiled water and tea; try not to drink sugary drinks, which will be converted into fat. After a lot of exercise, you can drink some sports drinks to replenish the inorganic salts lost with sweat.

How much water should an adult drink every day?

According to the recommendations of the "Dietary Guidelines for Chinese Residents (2016)", adults need 7 to 8 cups (about 1500ml to 1700ml) per day.

However, spring, summer, autumn and winter are different, and the work you do is different. In other words, if you consume more or sweat more, you need to drink more water every day. It is meaningless to discuss how much water you should drink every day.

I would like to say this: let your body tell you whether or not to drink water, and when to drink water. If you are thirsty, you will naturally want to drink water, so drink it. Don't make it difficult for yourself, water is not expensive, you can afford it; drinking more or less has nothing to do with being fat or thin.

The following five components of the human body will be discussed in detail later, so this article will be kept as brief as possible.

protein

About 15-20%. If the muscles are well developed, there is more protein. Any tissue and organ of the human body contains a lot of protein, such as skin, blood, muscles, internal organs, bones, and hair. The protein of various tissue cells is constantly being renewed, and sufficient protein needs to be taken in every day to maintain the renewal of tissues. It can also be said that there is no life without protein.

Fat

About 13-20%. There are great differences between individuals. For obese people, it can be as high as 60%, while for athletes, especially bodybuilders, it can be as low as 3-5%. Most of it is stored in adipose tissue in the form of triglycerides as an immediate energy source and reserve energy. Although too much fat can cause obesity, the human body cannot live without fat, especially essential fatty acids, which must be provided in appropriate amounts.

carbohydrate

The amount stored in the human body is very small, accounting for about 0.5%. However, the demand is very high. As an immediate energy source and emergency energy source, the more it is supplied, the more it is consumed. The main function of carbohydrates is to supply energy such as glucose to the body's tissues, especially the brain, nerves, myocardium, red blood cells, etc., which need glucose for energy. If the blood sugar supply is insufficient, the mild case will feel tired, and the severe case will suffer from hypoglycemia and coma.

Minerals

About 5-6%. It is the main component of bones and teeth, relatively stable, and fewer people suffer from osteoporosis. The 21 elements are considered to be minerals necessary for forming human tissues, participating in biochemical metabolism, and maintaining physiological functions. Minerals cannot be synthesized in the body and must be taken from the outside.

Vitamins

Very small, but indispensable. Vitamins are a class of organic compounds necessary to maintain the life processes of the body. Most vitamins cannot be synthesized in the body, nor can they be stored in large quantities in body tissues, and need to be obtained regularly from food.

After talking about the six types of chemical substances that make up the human body, now we need to eat the same substances that the human body is made of.

The nutrients the human body needs are the six types of chemicals that make up the human body: water, protein, fat, carbohydrates, minerals, and vitamins.

Please note that there are six types of substances, not six kinds of substances. How many kinds of substances are there? Each type of nutrient, except water, has many kinds of substances.

The functions, digestion, absorption and metabolism processes, nutritional evaluation, requirements, food sources, etc. of these nutrients will be introduced in the special topic.

There are two more concepts you need to know, which are rather boring, so I’ll include them at the end.

Nutrition: The science that studies the laws of human nutrition and measures to improve them, and discusses human nutrition and health issues.

Nutrition: refers to the process of digestion, absorption and utilization of food by the human body. It is the process by which humans meet their physiological needs by taking in food.

References:

[1] Chinese Nutrition Society. Dietary Reference Intakes of Nutrients for Chinese Residents (2013 Edition). Beijing: Science Press, 2014.

[2] Chinese Nutrition Society. Dietary Guidelines for Chinese Residents (2016). Beijing: People's Medical Publishing House. 2016