The methodology used in research of influence of
beverages (red wine, green tea) on human health


In contemporary society, with the remarkable improvement in growth of people’s living standard, the health of the human race arouses wider public concern. At present, cancer is one of the most terrible killers of people because of its high fatality rate. As a result, research into treatment for cancer has become a center of attention in science. Many scientists have focussed their research on the effect of some beverages (red wine, green tea) on cancer. This essay describes different methodologies used in the research of influence of beverages on human health. Specifically, investigated topics, approaches of the research and comparison methods will be addressed in the essay.

Firstly, the investigated topics on this issue mainly include red wine and green tea. To be exact, Suganuma.M et al (1999) studied the bioavailability of tea polyphenols with 3H-EGCG which was refined from green tea. Researching the influence of green tea on cancer as well, Nakachi.K et al (1998) surveyed 472 human patients in Japan using questionnaire instead of experiment. On the other hand, research focusing on red wine was done in Canada by doing the experiment (Soleas.J.G 2002). Likewise researching the effect of red wine on cancer, Viel J.F et al (1997) did an investigation within 154 patients in France. There were three studies on green tea being done in Japan and two being in China; while, three studies based on red wine were done in France and Canada, respectively. From the comparison mentioned above, it can be concluded that eastern countries such as China and Japan paid more attention on effects of green tea while western countries were concerned more about red wine, probably due to cultural differences in their diet.

Secondly, the approaches of the research show the diversity of the methodology. In terms of experimental research, for the purpose of obtaining the results of the effects of beverages on cancer, some researchers conducted experiments with cells; while, someone used animals as the subjects. More specific, in the study done by Soleas.G.J et al (2002), they used six groups of five CD-1 mice to evaluate the effectiveness of each of the four compounds. To be the case groups, five of the six groups were initially treated with DMBA which could induce tumors in mice. Meanwhile, the sixth group was used as control group receiving only acetone initially and biweekly. After that, they treated the animals who were previously treated with DMBA topically thereafter with one of the four compounds at different concentration twice a week over the following eighteen weeks. During the period of eight to ten weeks, the flanks were shaved weekly so that the developed tumors could be exposed. When tumors became numerous, shaving had to be discontinued to prevent infection. In contrast, Damianaki et al (2000) used three different human breast cancer cell lines: MCF7, T47D and MDA-MB-231. MCF7 and T47D are hormone sensitive, while processing a discrete pattern of estrogen and progesterone receptors, and MDA-MB-231 is hormone independent for growth. The cells were cultivated for six days and treated with polyphenols.

Lastly, some comparison methods were used in the methodology of the studies, observation and statistical analysis. To take the experiment done by Soleas G.J et al as an example, at the end of the experiment in the eighteenth week, researchers counted the tumors when the skin was carefully shaved to fully reveal all the lesions. By observing the tumors and comparison the subjects in each group, researchers could respectively assess the effects of the four compounds on the disease the mice got. By this method, researchers could clearly compare the results caused by the different compounds. However, the shortcoming of this method is that the sample size was not big enough which may lead to the results being affected by other factors such as the immunity of the samples before the experiment.
The other way used to compare the results is called statistical analysis. Sasazuki S. et al (2008) investigated over 100000 subjects who were asked to reply to a lifestyle questionnaire that covered sociodemographic characteristics, medical history, smoking and drinking habits, and diet. In the meantime, researchers collected blood samples from a fraction of the subjects including healthy people and patients for the following-up experiment. The blood samples were measured by chemical methods and the results were got as the level of several compounds in the blood samples. Lastly, researchers controlling some conditions such as smoking status at the same level, the net results got from the comprehensive analysis of the questionnaire data and blood-experiment figures. Such research using questionnaire could not avoid a problem that is the veracity of people’s respondence. That means the respondents may give a biased reply hiding something bad such as drug-taking. In this case, the results would be less reliable. Fortunately, the sample size in this research was quite big which was likely to deal with this drawback.

To sum up, this essay summarized the methodology of some previous researches in several aspects, investigated topics, approaches of research and comparison methods. The two main investigated topics were red wine and green tea. Additionally, some researchers managed their study based on animal experiments while some others did tests on cells. Observational comparison and statistical analysis were used to gain the conclusion. There was a great variety in techniques and these different approaches have contributed to understanding how we drink can effect our health. However, all of them had their own limitations. It is recommended for the deeper studies in the future, the investigated subject can be extended to other beverages such as influence of coffee on cancer.[/SIZE][/SIZE]