Drinking tea reduces non-cardiovascular mortality by 24%, reveals a study in 13,000 people presented at European Society of Cardiology Congress by Professor Nicolas Danchin from France.
Commenting on the study, Dr Carrie Ruxton from The Tea Advisory Panel (TAP) notes: “This study investigated the risk of cardiovascular and non-cardiovascular mortality in relation to tea and coffee consumption in a large population of French people at low risk of cardiovascular disease. The study included 131,401 people aged 18 to 95 years who had a health check up at the Paris IPC Preventive Medicine Centre between January 2001 and December 2008. During a mean 3.5 years follow up there were 95 deaths from cardiovascular disease (CVD) and 632 deaths from non-CVD causes. Tea consumption was assessed by a self-administered questionnaire as one of three classes: none, 1 to 4, or more than 4 cups per day.
“Compared to no tea drinking, tea drinking lowered the risk of non-CVD death by 24% and the trend towards lowering CV mortality was nearly significant. When the analysis was extended to 2011 tea continued to reduce overall mortality during the 6 year period. Most of the effect of tea on non-CV mortality was found in current or ex-smokers, while tea had a neutral effect in non-smokers.
“In this study, tea had a more marked effect on blood pressure than coffee, with a 4-5 mmHg decrease in systolic blood pressure and 3 mmHg decrease in diastolic blood pressure in the heavy tea drinkers, compared to non-drinkers, when adjusted for age. This effect of tea on lowering blood pressure has been found in several earlier studies. A meta-analysis of 25 randomised controlled trials published in the British Journal of Nutrition [1] involving 1476 people found that long term tea intake reduced systolic and diastolic blood pressure while acute tea intake had no effect. The blood pressure lowering effect was apparent in people who consumed tea for more than 12 weeks.
“Tea drinkers also had a better cardiovascular risk profile in this new study than people who did not drink tea. For example, tea drinkers had a healthier lifestyle. One-third (34%) of the people who did not drink tea were current smokers compared to 24% of those who drank 1-4 cups per day and 29% of those who drank more than 4 cups. Physical activity increased with the number of cups of tea per day from 43% in the moderate tea drinkers to 46% in the heavy drinkers.”
Dr Catherine Hood from TAP adds; “Overall this study adds to the growing evidence base that tea consumption reduces cardiovascular risk. This is likely related to the flavonoid content of tea. In addition to effects on blood pressure, a study published earlier this year found that drinking more than three cups of tea daily is associated with reduced arterial stiffness.[2] Other previous studies have shown that black tea improves blood flow through the arteries[3] and can reduce the risk of stroke.[4] Two recent meta-analyses have found that tea consumption improves cholesterol profile mainly by reducing LDL (bad cholesterol). [5] [6]
“Tea is a very popular beverage in the UK and these findings across several studies continue to suggest that Britain’s’ favourite beverage is good for cardiovascular health.”
References
[1] Gang Liu, Xue-Nan Mi, Xin-Xin Zheng et al. Effects of tea intake on blood pressure: a meta-analysis of randomised controlled trials. British Journal of Nutrition, 2014, doi:10.1017/S000711451400173
[2] Li C-H, Yag Y-C, Wu J-S et al. Increased tea consumption is associated with decreased arterial stiffness in a Chinese population. PLOS one January 2014, Issue 1, e86022.
[3] Grassi D, Mulder TP, Draijer R, Desideri G, Molhuizen HO, Ferri C. Black tea consumption dose-dependently improves flow-mediated dilation in healthy males. J Hypertens 2009;27:774e81.
[4] Arab L,,Liu W, Elashoff D. Green and black tea consumption and risk of stroke: a meta-analysis. Stroke 2009;40:1786e92.
[5] Zhao Y1, Asimi S1, Wu K1 et al. Black tea consumption and serum cholesterol concentration: Systematic review and meta-analysis of randomized controlled trials. Clin Nutr. 2014 Jun 13. pii: S0261-5614(14)00167-8. doi: 10.1016/j.clnu.2014.06.003. [Epub ahead of print]
[6] Hartley L, Flowers N, Holmes J, Clarke A, Stranges S, Hooper L, et al. Green and black tea for the primary prevention of cardiovascular disease. Cochrane Database Syst Rev 2013;6:D9934.