Is the nutritional value of dark-colored vegetables really greater than that of light-colored vegetables?

You can tell a vegetable's nutritional value just from its color. As we all know, there are many kinds of vegetables people commonly eat, but the colors of various vegetables are all different, some dark and some light. Many people think a vegetable's nutritional value has nothing to do with its color, but the fact is that dark-colored vegetables have higher nutritional value than light-colored ones. What is the reason behind this?

Countries around the world emphasize increasing the variety and quantity of vegetables

Vegetables and fruits are important sources of vitamins, minerals, dietary fiber and phytochemicals, with high water content and low energy. A diet rich in vegetables, fruits and tubers plays an important role in maintaining good health, keeping normal intestinal function, improving immunity, and reducing the risk of chronic diseases such as obesity, diabetes and high blood pressure. So in recent years, the dietary guidelines of various countries have all emphasized increasing the variety and quantity of vegetables and fruits consumed. Both the "Capital Citizens' Healthy Dietary Guidelines" and the "Dietary Guidelines for Chinese Residents 2007" recommend that Chinese adults eat 300 g-500 g of vegetables every day, preferably with dark-colored vegetables making up about half; 200 g-400 g of fruit, and pay attention to increasing the intake of tubers.

The nutrition of lettuce leaves, celery leaves and radish greens is several times higher than that of the stems and roots

Vegetables are an important source of micronutrients, dietary fiber and natural antioxidants. Generally, fresh vegetables contain 65%-95% water, and most vegetables have a water content above 90%. Vegetables contain cellulose, hemicellulose, pectin, starch, carbohydrates, etc., and most are low in energy, making them a low-energy food. Vegetables are also a good source of carotene, vitamin B1, vitamin C, folic acid, calcium, phosphorus, potassium and iron.

Tender stems, leaves and flowering vegetables such as Chinese cabbage, spinach and broccoli are good sources of carotene, vitamin C, vitamin B2, minerals and dietary fiber. Vitamin C is abundant in the metabolically active leaves, flowers and stems of vegetables, in parallel with the distribution of chlorophyll. Generally, dark-colored vegetables contain more carotene, riboflavin and vitamin C than light-colored vegetables, and contain more phytochemicals. In the same vegetable, the vitamin content of the leaves is generally higher than that of the roots and stems; for example, lettuce leaves, celery leaves and radish greens are several times higher than the corresponding stems and roots. The nutritional value of leafy vegetables is generally higher than that of melon vegetables. Root vegetables have lower dietary fiber than leafy vegetables. Cruciferous vegetables such as kale, cauliflower and cabbage contain phytochemicals such as aromatic isothiocyanates, which are the main cancer-inhibiting components. Mushrooms and algae such as tricholoma, shiitake, wood ear, yeast and nori contain protein, polysaccharides, carotene, iron, zinc and selenium and other minerals, and marine algae such as nori and kelp are also rich in iodine.

Dark-colored vegetables: a perfect combination of color, aroma, taste and nutrition

Dark-colored vegetables refer to dark green, red, orange-red and purple-red vegetables. They are rich in carotene, especially beta-carotene, and are the main source of vitamin A for Chinese residents. In addition, dark-colored vegetables also contain various other pigment substances such as chlorophyll, lutein, lycopene and anthocyanins, as well as aromatic substances, which give vegetables their special color, flavor and aroma, help stimulate appetite, and exhibit some special physiological activities.

Common dark green vegetables: spinach, bok choy, winter amaranth, celery leaves, water spinach (kangkong), lettuce leaves, mustard greens, broccoli, watercress, scallions, garland chrysanthemum, Chinese chives, radish greens, etc.

Common red and orange-red vegetables: tomatoes, carrots, pumpkins, red chili peppers, etc.

Common purple-red vegetables: red amaranth, purple cabbage, houttuynia, etc.