Who chooses the healthiest food sweet potato as the best vegetable? After three years of research and selection, the World Health Organization named the healthiest food as the best vegetable and the best fruit. The familiar sweet potato was listed as the 13 best vegetable champion. Sweet potato, whose hometown is South America, was introduced to China at the end of 16. People have different names for it in different areas, such as sweet potato and sweet potato. Today, there are traces all over China except the Qinghai-Tibet Plateau. There are many kinds of sweet potatoes, which are spindle-shaped, cylindrical, oval and spherical. The skin color is white, light yellow, yellow, red and purple, and the flesh color is yellow, apricot and purple. In recent years, after variety reform, sweet potato has become more delicious. Small sweet potatoes and big nutritious sweet potatoes contain many nutrients needed by human body. Every 500 grams of sweet potato can generate about 635 kilocalories, including protein 1/kloc-0.5 grams, sugar 14.5 grams, fat1gram, phosphorus 100 mg, calcium 90 mg, iron 2 g and carotene 0.5 mg. The contents of vitamin B 1 and B2 are 6 times and 3 times higher than those of rice, respectively. In particular, sweet potatoes are rich in lysine, which is the most lacking in conventional staple foods such as rice and flour. Sweet potato is sweet and rich in carbohydrates, dietary fiber, carotene, vitamins and potassium, magnesium, copper, selenium, calcium and other elements 10. Although sweet potato is small, it has great health care function, especially for the health of the elderly. Because sweet potato is an alkaline food, it is beneficial to maintain the acid-base balance of blood. Sweet potato contains a lot of mucin and mucopolysaccharide, which can keep the elasticity of human cardiovascular wall, prevent the occurrence of atherosclerosis and keep the lubrication of respiratory tract, digestive tract and joint cavity. In addition, the starch cellulose contained in sweet potato can absorb a lot of water in the intestine, which is beneficial to prevent constipation and reduce the occurrence of intestinal cancer. How does a small sweet potato become a "number one dish"? According to experts, sweet potato is not only nutritious, but also has the functions of preventing sub-health, bodybuilding and anti-cancer. Sweet potato has anti-cancer effect. The most anticancer nutrients in the diet are β-carotene, vitamin C and folic acid, and sweet potatoes are also rich in ingredients. A small sweet potato (about 2 times) can provide 2 times of daily vitamin A, 1/3 of daily vitamin C, and about 50 micrograms of folic acid, among which the dietary fiber content is higher than that of a bowl of oatmeal. The antioxidant effects of β -carotene and vitamin C are helpful to resist DNA damage caused by oxidative stress. Eating sweet potatoes regularly helps to maintain the normal folic acid level of the human body, and low folic acid content in the body will increase the risk of cancer. Sweet potato has high dietary fiber content, which can promote gastrointestinal peristalsis and prevent constipation and colorectal cancer. Sweet potato is good for the heart. Sweet potato is rich in potassium, beta-carotene, folic acid, vitamin C and vitamin B6, all of which help to prevent cardiovascular diseases. Potassium contributes to the balance of liquid and electrolyte in human cells and maintains normal blood pressure and heart function; β -carotene and vitamin C have the effects of anti-lipid oxidation and prevention of atherosclerosis. Supplementation of folic acid and vitamin B6 is helpful to reduce the level of homocysteine in blood, which can damage arterial blood vessels and is an independent risk factor for cardiovascular disease. Sweet potato can prevent emphysema. Animal experiments show that the level of vitamin A in smoking rats is low and emphysema is easy to occur, while the incidence of emphysema in smoking rats who eat foods rich in vitamin A is obviously reduced. Some long-term smokers live to be over 90 years old without emphysema, which is probably related to the rich vitamin A content in their daily diet. Researchers suggest that smokers or passive smokers should eat some foods rich in vitamin A every day, such as sweet potatoes, to prevent emphysema. Sweet potato has anti-diabetic effect: researchers found that the blood insulin level of diabetic obese rats decreased by 26% and 60% after eating white sweet potato for 4 weeks and 6 weeks respectively, and found that sweet potato can effectively inhibit the increase of blood sugar level of diabetic obese rats after taking glucose orally. Eating sweet potato can also reduce the levels of triglycerides and free fatty acids in diabetic rats. It is suggested that sweet potato with white skin has certain anti-diabetic effect. Does eating sweet potatoes make people fat? According to scientific research. Sweet potato will not make people fat, on the contrary, it is an ideal diet food. Its calories are very low, much lower than ordinary rice. You don't have to worry about getting fat after eating it, but you can lose weight. Sweet potato also contains a substance similar to estrogen, which has a certain effect on protecting human skin and delaying aging. So many foreign women regard sweet potato as beauty food.