托福独立写作范文：
Currently, the average life expectancy of the Earth’s population is at an all-‐time high. Many factors have contributed to this, but the main reason people live longer now than ever before is because it is easier to live a healthier life than in the past.
The main reason people live longer now is that the overall diet of modern society has improved. This can be attributed to advances in agricultural production. Thanks to more efficient and cost-‐ effective machinery and transportation, food is more abundant and cheaper now more than ever. Fruits, for example, are more readily available than before. In the past, summer fruits such as strawberries and oranges were not available during the wintertime. Now, because of refrigeration and greenhouse technology, we can buy any kind of fruit, regardless of the season. This allows people to have a wider variety of vitamins in their diet, increasing their overall health.
In addition to the advancement of agricultural science, there have been great advances in nutritional science. Scientists and dietitians understand more now than they did in the past about what is required in our daily diets. Issues like vitamin deficiency were not properly understood in the past, so people would have several complications without understanding the cause or the cure. People also better understand what foods to avoid. For example in the past, gout was a serious problem among men, who did not understand that a diet of rich and oily foods with few vegetables was the cause of this health defect. Now, proper nutrition is common knowledge and each year advances are made in understanding health. We know more know, so it’s easier for us to maintain our health.
Finally, it is easier to maintain our health now in the past, because modern governments have established better systems of health and sanitation. In the past, aspects of the health system, like medical education and research, were not well organized. In the past doctors received their degrees from institutions that all had varying requirements. Now there is a more established system of medical education, including international standards and guidelines. Governments play a large part in implementing these standards. Other systems of health regulation that governments have established is sanitation. Before people understand the importance of proper waste disposal, cities were susceptible to devastating plagues. In modern times, through proper sewage systems, waste disposal, and other health quarantine measures governments have been able to effectively contain diseases and help save the lives of many people. These systems have made it easier to keep the general popular safe and healthy.
With the advancement and development of food production, nutritional science, and government systems of health and sanitation has made it more possible than ever for people to lead long and healthy lives. (460 words)