Positive effects of coffee consumptions on peoples health 1 / 6AbstractCoffee becomes one of the most important international trades during nineteenth century. Coffee is a kind of Subtropical Crops that contains different kinds of water-soluble components, and the quality of coffee should be associated with soil conditions, growing environment, field management, the types of beans. Nowadays, more and more people pay attention to the health beverage, and coffee is beneficial to peoples health in some aspects. According to many recent researches, they demonstrate that coffee has health care functions. A cup of coffee in the morning can help to refresh, and helps to lose weight if we drink after lunch. Coffee plays a vital role in preventing Parkinsons disease and Colorectal Cancer, and resisting heart disease. According to the study, we should enjoy coffee reasonably or it will cause some negative effects on our bodies.I. IntroductionIt is generally believed that coffee originated in Kaffa Ethiopia at around 600 AD, and now coffee is an indispensable beverage in our daily life. People could consume 400 billion cups of coffee all over the world, and there were more than 500 hundreds of people undertake coffee planting just in Brazil. (Wang ZQ, 2006). Coffee is a complex chemical mixture that contains hundreds of healthy ingredients, they have some positive effects on humans health, such as removing tiredness, protecting the heart and blood vessels, accelerating metabolism, eliminating fatigue. In the following paper, I intend to focus on the compositions of coffee and some recent researches of the positive effects of coffee on peoples health.II. The compositions of coffeeAccording to the professor Wang Zhaoqiang(2006), coffee water-soluble components are as follows: 8% poly-phenol (plasma), 6% polysaccharide, 4% chlorogenic acid, 3% minerals, 2% water, Positive effects of coffee consumptions on peoples health 2 / 61% caffeine, 0.5% organic acids, 0.3% sugar, 0.2% lipid, and 0.1% aromatic compounds. I wander to explain more about two main compositions of coffee which are little in coffee but have great impacts on human health.1. CaffeineAs everyone knows caffeine is the most compelling component of coffee. The molecular formula of caffeine is C8H10N4O2 , and its chemical structure shows in the following figure.(Spiller,M.A.1998. The Chemical Components of Coffee).It is a kind of purine alkaloid that widely exists in coffee, tea, and some chocolates. The standard of caffeine content in food and drink has been set already. The contents of caffeine are different in different kinds of decorated drinks. For example, 150ml cup of ground coffee contains about 85mg, instant coffee contains 60mg, decaffeinated coffee contains 3mg, tea contains 30mg, instant tea contains 20mg, and cocoa or hot chocolate, caffeine-contains only 4mg. (Barone, J.J. Roberts, H.R. Food and Chemical Toxicology). 2. Chlorogenic acidExcept caffeine, another important composition is named chlorogenic acid which is widely distributed in plants, mainly exists in Lonicera, Artemisia, such as coffee and cocoa trees. Its molecular formula is C16H18O9. (Spiller,M.A.1998. The Chemical Components of Coffee). Coffee should drink as soon as possible after cooked, because the acid can decompose and produce Jiao Wu acid after boiling, and the coffee will taste worse. Positive effects of coffee consumptions on peoples health 3 / 6Chlorogenic acid is considered as the main proprietary Chinese medicine antibiotic detoxification. It can be used to cure liver disease and lower cholesterol levels in some countries. It can also help to prevent lung from being injured by ozone.III. The positive effects of coffee on humans healthIn fact, caffeine has numerous effects on humans. In medicine, it is a central nervous system stimulant and metabolic irritant; it plays an crucial role in refreshing and removing of fatigue, and also reducing pain of your headache. Caffeine is popular in manufacturing medicine. Many recent researches indicate that in many aspects coffee does not have those hazards as people imagine before. There is no doubt that caffeine in daily life can significantly improve peoples sobriety. More and more evidences indicate that coffee can help people to keep awake. In addition, coffee has other plenteous positive effects.1. Prevention of Parkinsons diseaseMany cases have indicated that drinking coffee can help to reduce the risk of Parkinsons disease, in order to corroborate this theory, two organization HPFS and NHS performed experiment to study the relationship between coffee consumptions and Parkinsons disease. There were 47351 men and 88565 women who did not have medical history of Parkinsons disease participate the experiment. All participants had to finish a investigation qu