Basic knowledge of food nutrition and dietary balance

Basic knowledge of food nutrition

I. Basic Nutrients in Food

The basic nutrients in food are as follows:

Proteins: Their functions include building and repairing body tissues, forming components of enzymes and hormones, regulating physiological functions, and forming antibodies to help the body fight disease.

Main sources: Eggs, lean meat, fish, poultry, milk, etc., which contain high-quality protein; soybeans, dried beans, peas and other nuts; grains, pasta and some vegetables.

Carbohydrates: Their functions include providing energy and heat for movement and circulation, building body tissues, and storing proteins for tissue construction and repair.

Main sources: starch; grains and grain products; rice, corn, dried beans, potatoes, dried fruits, bananas; sugars such as sucrose, syrup, honey, jam, jelly, rock sugar, candy, icing sugar and other confectionery products.

Fat: Its functions include providing concentrated energy (equivalent to twice the weight of carbohydrates), helping the body utilize fat-soluble vitamins (A, D, E, K), and providing structural elements for cell membranes throughout the body.

Main sources: vegetable oils, butter, margarine, egg yolks, salad dressings, fatty meats, fried foods, most cheeses, whole milk, nuts, chocolate, and coconut.

Riboflavin (vitamin B2): Its functions include helping human cells use oxygen and obtain energy from food, helping to maintain eye health, and helping to keep the skin around the mouth smooth.

Main sources: milk and dairy products, animal liver, heart, lean meat, eggs, dark green vegetables, dried beans, almonds, and grains (many foods contain small amounts of riboflavin).

Niacin (vitamin B3): Its functions include helping human cells use oxygen and obtain energy from food, helping to maintain healthy skin, digestive and nervous systems, and helping to maintain the growth of cells and tissues throughout the body.

Main sources: fish, poultry, liver, lean meat, peanuts, bread fortified with vitamin B3, grains, and legumes.

Vitamin D: Its functions include helping the body use calcium and phosphorus to build and maintain strong bones and teeth, and promoting normal human development.

Main sources: cod liver oil, milk, UV-dehydrated condensed milk, liver, egg yolk, salmon, tuna, sardines (direct sunlight can also help the body produce vitamin D).

Vitamin B6: Its functions include helping the body use proteins to build human tissues, helping the body use carbohydrates and fats to produce energy, and helping to maintain the skin and the recovery of the digestive and nervous systems.

Main sources: pork, liver, heart, kidney, milk, concentrated grain products, malt, beef, yellow corn, bananas.

Folic acid: Its functions include helping the body produce red blood cells and aiding in cellular metabolism.

Main sources: liver, lettuce, orange juice.

Vitamin A: Its functions include helping to maintain eye health and enhance vision in the dark; helping to maintain healthy and smooth skin; helping to maintain the health of the mouth, nasal cavity, throat, and digestive system and fighting infection; and helping normal bone development and teeth formation.

Main sources: liver, butter, vitamin-fortified margarine, egg yolks, whole milk, vitamin A-fortified milk, dark yellow and dark green leafy vegetables, Roman melon, apricots and other dark yellow fruits.

Vitamin C: Its functions include helping to synthesize human cells, strengthening cell membranes, enhancing normal bone and teeth formation, aiding in wound and bone damage recovery, aiding in iron absorption, and helping to fight infection.

Main sources: citrus fruits and juices, strawberries, Roman melons, watermelons, tomatoes, flower stalks, sugarcane, green peppers, and cauliflower, sweet potatoes, yams, and raw cabbage are also rich in vitamin C.

Thiamine (vitamin B1): Its functions include improving normal appetite and digestion, helping the body convert carbohydrates in food into energy, and helping to maintain a healthy nervous system.

Main sources: lean pork, heart, kidney, dried broad beans, peas, vitamin-fortified bread and cereals, and certain nuts.

Vitamin B12: Its functions include helping human cells function normally and aiding in the regeneration of red blood cells.

Main sources: liver, kidneys, milk, eggs, fish, cheese, lean meat.

Calcium: Its functions include helping to strengthen bones and teeth, helping to improve the normal function of nerves, muscles and heart, and helping to ensure normal blood clotting.

Main sources: milk, cream, ice cream, sardines, clam meat, and also contain considerable amounts of calcium in dark green leafy vegetables and oysters.

Iron: Its functions include combining with proteins to form hemoglobin, transporting the oxygen needed by the body to all parts of the body, helping cells absorb oxygen, and preventing iron-deficiency anemia.

Main sources: liver, heart, lean meat, shellfish, dark green leafy vegetables, egg yolks, dried peas, broad beans, dried fruits, grain crops, vitamin-fortified bread, as well as cereals and syrups.

Iodine: Its functions include helping the thyroid gland to function normally and helping to prevent certain types of goiter.

Main sources: iodized salt, seafood.

Phosphorus: Its functions include helping to strengthen bones and teeth, being an essential component of all human cells, helping muscles function properly, and helping the body absorb and utilize sugars and fats.

Main sources: meat, poultry, milk, eggs, dairy products, nuts, dried broad beans, and peas.

II. Balanced Diet

In 1998, my country issued its first "Chinese Dietary Guidelines Pagoda" tailored to its national conditions, providing guidelines for making reasonable food choices.

The balanced diet pyramid has five layers, which include the main types of food we should eat every day.

The different positions and sizes of the various layers of the pagoda reflect, to some extent, the status and proportion of different types of food in the diet.

Grains are at the bottom, with each person consuming 300 to 500 grams per day; vegetables and fruits occupy the second layer, with each person consuming 400 to 500 grams and 100 to 200 grams per day respectively; animal-based foods such as fish, poultry, meat, and eggs are in the third layer, with each person consuming 125 to 200 grams per day (50 grams of fish and shrimp, 50 to 100 grams of livestock and poultry meat, and 25 to 50 grams of eggs); dairy products and legumes occupy the fourth layer, with each person consuming 100 grams of dairy products and 50 grams of legumes per day.

The fifth tier, the top layer, consists of oils and fats, and each person should consume no more than 25 grams per day.