The effect of short term consumption of antioxidant rich fruit tea on respiratory and cardiovascular parameters.
Background: A growing body of research indicates that consumption of food high in polyphenols and antioxidants plays a major role in disease prevention. Antioxidants can prevent the extensive damage caused by oxidative stress. Uncontrolled oxidative stress can be responsible for irreversible damage and an abundance of many chronic and degenerative diseases. Therefore, a diet high in antioxidants may be associated with improved lung function parameters (VC, FVC, FEV1 and FEV1/FVC ratio) as well as decreased risk factors for cardiovascular disease including hypertension, diabetes and hyperlipidemia. There is limited evidence to demonstrate the effect of berry fruit tea on lung function and cardiovascular disease and the relationship between berry tea and these conditions is yet to be determined. Aim: The overall aim of this research was to determine the effect of berry fruit tea consumption on lung function and blood pressure in a healthy female population. Methods: Fourteen healthy females (age; 22.21±2.64 and BMI; 23.61±2.54) were selected for the study. Prior to the start of the intervention, various fruit teas and a green tea for the purpose of a control (Asda strawberry and forest fruit, Asda wild berry, Tetley superfruit boost, Twinings cranberry and raspberry and Asda green tea) were analysed in the lab using FRAP and Folin assays. The tea highest in antioxidant and polyphenolic capacities was chosen to be used in the intervention. The intervention required participants to consume 2 cups of the selected tea for a week and complete a 4 day diet diary and a physical activity questionnaire. Blood pressure measurements were taken using the blood pressure monitor before and after the intervention. Lung function measurements including VC, FVC, FEV1 and FEV1/FVC ratio were taken pre and post intervention using vitalograph apparatus. Results: Overall, the statistical analysis of pre and post measurements of blood pressure and lung function showed no significant difference with all p values being greater than 0.05. Additionally, the laboratory tea analysis showed all fruit teas had similar antioxidant and polyphenol capacities, however further analysis of statistical significance using an ANOVA test would be necessary. Conclusion: In conclusion, a one week intervention consisting of the consumption of 2 cups of antioxidant rich berry fruit tea per day showed no significant improvement in lung function or blood pressure in a healthy female population. Considering a more significant improvement is more likely to be seen in the unhealthy populations, it may be beneficial to change the focus of this study to individuals with low antioxidant diet or people suffering from asthma, COPD or hypertension in future research.