It is found that some bioactive substances necessary for human health will denature, inactivate and lose their functions when they meet the temperature above 55℃. Therefore, in some developed countries, eating vegetables raw is a very popular way to eat. Eating raw vegetables can retain the nutrition in vegetables to the maximum extent, and has the functions of preventing cancer and many diseases, because most vegetables contain an immune substance-interferon inducer, which can produce interferon by acting on the interferon gene of human cells, become the "guardian" of human cells, and have the functions of inhibiting cancer and antiviral infection of human cells. But this "interferon inducer" can't withstand high temperature, and only raw vegetables can play a role. Therefore, all vegetables that can be eaten raw are best eaten raw; Don't fry vegetables that can't be eaten raw, and try to reduce the loss of nutrition.

Vegetables suitable for raw food are carrots, cucumbers, tomatoes, sweet peppers, lettuce, cabbage, cabbage, eggplant, cauliflower, peppers, onions, celery and so on. Besides making salad, you can also make your own fresh vegetable juice, or make fresh vegetables into cold salad. It's best not to peel raw cucumbers, and don't scald tomatoes, because vitamin C will change after scalding and taste very sour. Raw lettuce is best peeled and washed first, then scalded with boiling water, mixed with seasoning and pickled 1~2 hours before eating. Eating raw vegetables should pay attention to the unity of nutrition, health and hygiene, and beware of "illness from the mouth". Be sure to choose fresh vegetables and be clean. Clean and disinfect your hands before cooking; Raw and cooked food should be opened separately; Wash vegetables and meat separately to avoid cross infection. When vegetables are cold-mixed, vinegar, garlic and Jiang Mo can be added, which can both flavor and sterilize. Some vegetables are not suitable for raw food. First, vegetables rich in starch (such as potatoes, taro, yam, etc.). ) must be cooked, otherwise the starch granules will not be broken and the human body cannot digest it. Second, vegetables containing some harmful substances, such as seeds of leguminous vegetables and potato chips, contain a kind of toxic protein called lectin, which can agglutinate red blood cells in human blood and even cause nausea, vomiting, diarrhea and even death in severe cases. When cooked thoroughly, toxic protein will lose its toxicity and be safe to eat. The third kind is green leafy vegetables that grow in the ground. Under normal planting conditions, this vegetable is often splashed by human and animal feces and pesticides, causing pollution. Wash it with clean water, but it won't be clean. Of course, if these vegetables are produced under soilless culture conditions, they can be eaten raw with confidence.