Obesity and prevention and treatment of cardiovascular diseases eat sweet apples; People with diabetes can eat sour apples; Treat constipation and eat ripe apples; Diarrhea should be eaten with raw apples. Ancient saying: Guo, a scholar in Jin Dynasty, wrote Guang Zhiyun: there are three kinds of white and green apples, Zhang Ye has white apples, and Jiuquan West (then India) has red and green apples. Liu Xi, a scholar at the end of Han Dynasty, wrote this name: Bai Zuo. It has the effects of promoting fluid production, moistening lung, invigorating spleen and stomach, and nourishing heart, so apples have always been people's favorite fruit. However, the further understanding of apple, especially its nutritional value, depends on the analysis and research of modern science. It is known that apples contain protein fatty carbohydrates, vitamin A, vitamin B 1 vitamin B2, vitamin C, carotene, calcium, magnesium, phosphorus, iron, zinc, potassium, selenium, malic acid, citric acid, tartaric acid, tannic acid, nicotinic acid, mucus and so on. It is also gradually realized that modern people are most concerned about the obesity problem in recent years, so many people mistakenly think that fruit contains sugar and is one of the sources of calories. In fact, apple is a low-calorie fruit. According to different varieties, the sugar content is between 10% ~ 15%, including fructose 6.5% ~ 1 1.2%, glucose 2.5% ~ 3.5% and sucrose/kloc. Malic acid can decompose fat in human body, prevent obesity and make skin soft and smooth; The content of protein in apples is four times that of pears. Because the nutrients in apples are easily absorbed, the zinc content in apples is high. Zinc is a component of many important enzymes in human body and an important element to promote children's growth and development. Is it beneficial for children to eat apples or is it an indispensable element of nucleic acid and protein? Eating more apples can promote brain development and enhance intelligence and memory. Indian doctors have a special study on the normal retina of human eyes, which contains 7 micrograms of selenium. The selenium content in eagle eye retina is 100 times that of human, which shows that eagle's keen vision is related to high selenium content. Some people can't see clearly at dusk, because the lack of vitamin A reduces the synthesis of rhodopsin, resulting in apples containing vitamin A and trace element selenium. Then, eating apples often can protect your eyesight. French medical scientists found that malic acid can lower cholesterol, and malic acid can combine with intestinal cholic acid to prevent intestinal cholic acid from being reabsorbed. So as to promote the conversion of cholesterol in blood into cholic acid, and has the function of lowering cholesterol. In addition, pectin, vitamin C and cellulose contained in apples can also lower cholesterol. Eating 300g apples a day can gradually reduce the originally high cholesterol. Apples are rich in potassium salts. After entering human blood, sodium salts can be replaced and excreted, which is beneficial to reducing hypertension and protecting arteriosclerosis, coronary heart disease and cerebrovascular diseases. Take 100g each time, three times a day for several days. Soluble fiber in apples can regulate blood sugar, which is also good for diabetics. Apples are also rich in vitamin C and iron. There is no doubt that it is a good food for anemia patients. Slicing apples, adding black tea and rock sugar, brewing in boiling water and drinking at will are all health-care apple teas. American Reader's Digest magazine once introduced 10 kinds of apples which are most beneficial to health. Among them, Apple ranked first. It is said that apples are rich in fiber, which can supplement enough fiber for human body, reduce the incidence of heart disease and lose weight. Many Americans think that fruit is a necessity to lose weight. They go on a diet one day a week and only eat apples that day. A Singaporean summed up the experience of eating apples: obese people eat sweet apples to prevent cardiovascular diseases; People with diabetes can eat sour apples; Treat constipation and eat ripe apples; The experiment of eating raw apples to treat diarrhea proves that eating fresh apples before going to bed can eliminate bacteria in the mouth and improve renal function; Squeezing raw apples into juice can prevent cough and hoarseness; Apple puree is an excellent prescription for treating indigestion in children and the elderly. Apples are rich in nutrition, which can strengthen the body and prevent and treat diseases. Canada's Reader's Digest also said that malic acid contained in apples has seven benefits to human body: enhancing digestive function; Reduce the level of harmful cholesterol; Enhance heart function; Lowering blood pressure (maintaining normal blood pressure); Maintain normal blood sugar level; Prevent the formation of cancer cells; Whiten skin, keep skin smooth and moist, and remove heavy metals from the body. In addition, pectin is a kind of soluble fiber, which can combine with cholesterol and excrete excess cholesterol from the body. Studies by American medical scientists have confirmed that apples can also treat depression, because the aroma of apples has a great influence on people's psychology and has an obvious effect on eliminating psychological depression. Clinically, it can make depressed people disappear after smelling the aroma of apples. Insomnia patients eat an apple before going to bed or smell its fragrance for a while, which has a calming effect on the nerve center and can fall asleep quickly.