Blood-skinned vegetables are often sold in farmers' markets. I used to have this cold dish when I went to eat. Occasionally bought raw, mixed to eat, slightly medicinal, crispy and delicious. However, I used to watch the program of Yangshengtang every day, and Yu Kang, a professor of nutrition, taught health knowledge as a guest many times. He advocated not eating some wild vegetables. Among them, there is a kind of pA substance in Hypericum japonicum, Pteridium aquilinum and Hypericum japonicum, which is an alkaloid, toxic to the liver and does have cancer risk. In addition, when I was young, I didn't know whether my life was too bad or other reasons. I am very allergic to purple scars. Once I was mixed with blood-stained vegetables, and the purple scar became more and more scary. An old man told me that food is bloody and you can't eat it casually. In view of this, I never eat blood-stained vegetables, and I doubt its medicinal effect of ascorbic acid.

Folks believe that Gynura divaricata has the effect of cooling blood and removing fire, and it is a kind of health-care vegetable beneficial to human health. Tested by the Experimental Center of the Academy of Agricultural Sciences, every 100g of Undaria pinnatifida contains 9 1.49 ~ 9 1.66g of water, 6.26 ~19.18g of crude protein and 22.5mg of ascorbic acid. It is rich in mineral nutrients, especially trace elements such as iron, copper and zinc (table 1-2). It also contains flavonoid glycosides, which is non-toxic, has the effects of prolonging ascorbic acid and reducing vascular purple, and has moderate resistance to malignant growth cells.