Everyone knows that eating more leafy greens is good for your health, and replacing some red meat with white meat is also beneficial. Why are leafy greens good? Is the lighter the color of the meat, the better it is?
In fact, it's not just leafy greens; dark-colored vegetables are more nutritious. Dark-colored vegetables refer to those that are dark green, red, orange-red, or purplish-red. The Chinese Nutrition Society recommends that you should eat half a jin (about 250g) of vegetables daily, with dark-colored vegetables accounting for more than half of that. Why is it emphasized that a certain amount of dark-colored vegetables must be guaranteed? The latest national nutrition survey data shows that when comparing the top 15 most commonly eaten dark-colored vegetables with the top 15 most commonly eaten light-colored vegetables, the vitamin C content in the dark-colored ones is twice as high as in the light-colored ones. Although the nutritional content is not exactly the same between different varieties of vegetables, for the same type of vegetable, the darker variety is more nutritious. For example, the beta-carotene content in broccoli is much higher than in cauliflower, and the iron content in black beans and black fungus is significantly higher than in soybeans and tremella. This difference is most pronounced in purple vegetables rich in anthocyanins. Common examples include dark purple eggplant versus light green eggplant, purple onion versus white onion, purple cabbage versus green cabbage, and purple sweet potato versus red or white sweet potato—the nutritional value of the former is significantly higher than the latter.
Even for the same vegetable, the darker the color, the better it is. For example, compared to the light green stalks of bok choy, its dark green leaves are more nutritious. Similarly, compared to the white stalks of a scallion, its green leaves are better; and compared to the white heart of a Chinese cabbage, its green outer leaves are superior. In daily life, people often discard the green scallion leaves in favor of the white stalks, or prefer the cabbage heart over the leaves, unknowingly falling into a nutritional误区 (mistake). Therefore, nutritionists remind everyone to eat more dark-colored parts of vegetables.
The nutritional assessment of meat is, in contrast, the opposite of that for vegetables; it's best to choose the lighter-colored ones. The lighter the color of the meat, the higher its nutritional value. For instance, the meat of fish, shrimp, crab, and shellfish, which is nearly transparent, has the highest nutritional value. They contain all the protein the human body needs, their amino acid composition is very close to the body's requirements, and they are the easiest for the gastrointestinal system to digest and absorb. In general meat, the saturated fatty acid content is high, whereas the fat in "transparent" seafood is mostly unsaturated fatty acids. In particular, EPA can prevent blood clots and is quite effective in preventing arteriosclerosis and hypertension. DHA has a special effect in improving intelligence and judgment and preventing brain aging. Aquatic and seafood products generally contain various vitamins and abundant minerals such as calcium, phosphorus, potassium, iron, iodine, and selenium—these are the micronutrients that modern people often lack.
Slightly darker in color than seafood meat are the meats of poultry like chickens and ducks, which are light red. Their nutritional value is second only to seafood. Their amino acid composition is similar to that of fish. Although their content of unsaturated fatty acids and minerals is not as high as in "transparent" meat, they are still highly recommended. The meat with the deepest color, a bright red, is the least nutritious, such as pork, beef, and mutton. Because they contain more saturated fat and higher cholesterol, they can easily lead to many chronic diseases and should be the meat eaten the least.