There are thousands of varieties of food in the world, in a dazzling array of colors. Nutritionists classify them into five major categories.
White
Rice, flour, and others. They provide the human body with more than ten nutrients such as starch, protein, and vitamins. After digestion and absorption, they sustain life and activity, but they often lack certain essential amino acids required by the human body.
Green
Various fresh green vegetables, fruits, and legumes, such as celery, bok choy, chives, mustard greens, spinach, green peas, mung beans, and green apples. They provide various vitamins and dietary fiber, which directly regulate many physiological functions in the human body, such as visual acuity and immunity.
Yellow
Soybeans, peanuts, and others contain a large amount of plant protein and unsaturated fatty acids. They are excellent high-protein, low-fat foods, and are most suitable for middle-aged and elderly people with high blood lipids.
Red
Red rice, red beans, sweet potatoes, tomatoes, carrots, red chili peppers, red dates, red apples, as well as various poultry, livestock, fish, and shrimp. Scientific research suggests that most red vegetables contain beta-carotene. Together with other red pigments in red foods, beta-carotene can enhance the activity of cells in human tissues. Therefore, eating more red foods can improve the body's ability to prevent and resist colds. Common sayings such as "eat three dates a day, and you'll never look old," "have sweet potatoes in your meal, and your face will be rosy," and "eat a chili when you're feeling cold, and a cold will naturally disappear" are all vivid summaries of the health benefits of red foods. Red fish and meat are sources of high-quality protein, fat, and many inorganic salts and trace elements.
Black
Black rice, black sesame seeds, black fungus, black buckwheat, black bread, black soybeans, black grapes, black pine nuts, black mushrooms, and Silkie chicken, cuttlefish, kelp, and fat choy (black moss). Modern medicine believes that black foods are not only rich in nutrition but also have health-preserving, beauty-enhancing, anti-aging, and longevity-promoting functions, earning them the name "longevity foods." For example, black rice contains many amino acids, vitamins, and minerals that the human body cannot synthesize on its own, and has effects such as nourishing yin and kidneys, strengthening the spleen and warming the stomach, invigorating blood, and improving eyesight. Black sesame seeds have an oil content of over 50%, the highest among grains, and are also rich in protein, calcium, and iron, with particularly excellent effects for nourishing the liver and kidneys and preserving youth and resisting aging. Black fungus has the special function of moistening the lungs, cleansing the gastrointestinal tract, and helping to digest fibrous substances.
A friendly reminder:
On the market, some people take advantage of people's preference for colorful food by adding artificial pigments to foods with duller colors. For example, tanghulu (candied haws), white steamed buns, and some water-soaked dried vegetables and seafood in farmers' markets are also soaked in inedible chemical pigments. These artificial synthetic pigposes a serious threat to human health, especially the health of teenagers. Therefore, when purchasing, be sure to distinguish the real from the fake.