The Epidemiological Studies On The Edible Condition And Safety Of Guangdong Herbal Tea

Over the past decades, the market for the herbal tea has developed very rapidly. Global salesof herbal tea in2010were more than that of Coca-Cola, so that the food safety must beguaranteed more strictly. The toxicology tests including the first, second, third phases of safetyevaluation showed that some Guangdong herbal tea had no acute toxicity, subchronic toxicity,mutagenicity and teratogenicity. The Guangdong herbal tea (GHT) was founded in1828.TheGuangdong residents had drunk it for more than180years and people all over the country haddrunk the certain brand herbal tea for a decade. These evidences demonstrated herbal tea wassafe to drink. However, there was a lack of scientific epidemiological studies about the safety ofherbal tea. In the support of State863projects, a cross-sectional study and an experimentalepidemiological study about the edible condition and safety of a certain brand herbal tea werecarried out, in order to provide the evidences in population for the safety of herbal tea.Objectives1. To investigate the edible condition of herbal tea in Guangdong residents;2. To demonstrate the safety of herbal tea.Methods and materials1. MethodsThis study contained both a cross-sectional study and an experimental epidemiological study.The cross-sectional study obtained the informations through the questionnaire investigation incommunity and the experimental epidemiological study through human feeding trials.2. Subjects2.1Cross-sectional study: residents lived in one of communities of Guangzhou and ZhaoqingCity for above five years, and were12to60years old. And no patients with significant mentalillness or dysnoesia. 2.2Experimental epidemiological study:18to28years old students lived in the university, withbody mass index of18to28, and did not participate in similar feeding trials in the past one year.No patients with severe diseases in cardiovascular system, digestive system, urinary system, andso on.3. Contents3.1Cross-sectional studies:(1) demographic characteristics, such as gender, age, educationallevel, etc.(2) the edible condition of herbal tea, such as the rate, the number of years, thefrequency, the habit, etc.(3) physical condition, such as the common symptoms ofgastrointestinal and respiratory tract and emotion status, and the common chronic diseases.3.2Experimental epidemiological study:(1) physical condition items, such as height, weight,blood pressure, heart rate, electrocardiogram, abdominal ultrasound, X-ray film, urine routine,stool routine, blood routine, liver and kidney function, lipid classification and so on.(2)9typesof constitution style in traditional medicine Chinese.(3) the information of follow-up, such asdaily edible situation, stool and urine situation, symptoms and signs, mental and psychologicalfeelings.4. Statistical methodsData were double entered by Epidata3.1and analyzed by SPSS16.0.Results1. Cross-sectional study1.1The effective return-ratio of questionnaire was97.9%(2154/2200).Male accounted for44.4%and the average age was33.5±14.9years old in2154respondents.1.2The drinking rate of all herbal tea was97.8%(2107/2154). The drinking rate of a certainbrand herbal tea was80.5%(1735/2154), and the average years of drinking were5.4±4.0, and80.5%of the drinker drunk one to four boxes per month.1.382.6%of the respondents drunk herbal tea mainly when they got excessive internal heat,29.9%～46.0%when the weather was too hot or they were thirsty or had a cold or a cough. Thedrunker mainly drunk herbal tea in normal temperature and mainly after a meal, and mainly inthe afternoon, and mainly in summer. 1.4There were no statistical differences on the drinking rates of a certain brand herbal teabetween the patients with chronic diseases and the normal subjects，and between the subjectswith some gastrointestinal symptoms and the normal subjects. But the drinking rate of subjectswith excessive internal heat symptoms were higher than normal subjects(P＜0.05), such as thirstand polydipsia, bubble blister or erosion in the angle of mouth, acne in the face, yellow or turbidurine, dry stool.2. Experimental epidemiological study2.1There were no Statistical differences between the treatment group and the control group inthe general condition such as gender, age, body mass index, etc. During the experiment, therewas no body to dropout.2.2The physical examination indexes of two groups were normal or had no clinical significance,and abnormal rate of physical examination indexes were not significantly different in statisticsboth before and after the experiment.2.3Between two groups, the prevalence rates of9constitution types in traditional medicineChinese before the experiment and the prevalence rates of8constitution types after theexperiment were not significantly different in statistics. In the end of experiment, the differencein prevalence rate of qi deficiency constitution had no practical significance between two groups.2.4During the experiment, there were no Statistical differences in the incidence rates of thefollow-up symptoms between two groups, such as symptoms of respiratory system, digestivesystem, urinary system, and emotion status, and so on.Conclusions1Most Guangdong residents had the habit of drinking herbal tea for a long term. And theresidents would drink herbal tea when they got the excessive internal heat symptoms.2Drinking herbal tea for a long term was not harmful to physical health, such as digestivesystem, respiratory system and urinary system, and so on.3Drinking herbal tea frequently for a short term had no significant influence in physical health, such as digestive system, respiratory system, urinary system, and cardiovasdular system andemotion status.