Tea is the second most consumed beverage worldwide after water, and is consumed by more than two-thirds of the world population (Dou, 2019)
The Good
In 2014 Xuguang Guo’s research team found that compared to nondrinkers, drinking tea without any sweetener was associated with a lower risk for depression and that adding artificial sweeteners, but not sugar or honey, was associated with higher risks.
Suzanne Einöther, and Vanessa Martens 2013 review of the effects of tea and reported consumption of tea consistently improved self-reported alertness and arousal. It positively affected the pleasantness of mood immediately after consumption. It had beneficial effects in related areas such as work performance and creativity. In fact, they reported that it showed faster insights on difficult problems than drinking water.
Einöther, and Martens (2013) reported that it also helped with stress management in the workplace. They described that participants in workplace research who consumed more tea felt less tired and reported that they performed well at work more often than participants who drank less tea—but only if it was consumed without milk and/or sugar.
It’s just great to drink with friends!
The Bad
Over consuming caffeine from tea ( or any other source) may contribute to feelings of anxiety (Temple et. al., 2017)
The caffeine in tea may affect sleep (O’Callaghan et. al., 2018)
The tannins in tea affect iron absorption (Delimont et. al., 2018), and low iron is associated with low mood (Korkmaz, et. al. 2015 and Vulser, et. al., 2016). This is particularly important to anaemia sensitive individuals.
The Ugly
The Tannins in tea can lead to nausea or stomach ache (Hussain, 2019). In high consumption or with sensitive individuals the caffeine in tea can cause headaches (Willson, 2018).
Summary
There is some good news, caffeine is usually much lower in tea (Chin, 2008) than coffee. People report a number of positive effects including creativity and less workplace stress. However, more is not better. Disappointing as it might be, moderation is the key. As you can see, there are lots of positives to tea. Including creativi-tea (this blog written while consuming tea!)
References
Guo X, Park Y, Freedman ND, Sinha R, Hollenbeck AR, Blair A, Chen H. Sweetened beverages, coffee, and tea and depression risk among older US adults. PLoS One. 2014 Apr 17;9(4):e94715.
Dou Q. P. (2019). Tea in Health and Disease. Nutrients, 11(4), 929. https://doi.org/10.3390/nu11040929
Einöther, S. J., & Martens, V. E. (2013). Acute effects of tea consumption on attention and mood. The American journal of clinical nutrition, 98(6 Suppl), 1700S–1708S. https://doi.org/10.3945/ajcn.113.058248
Gilbert N. (2019). The science of tea’s mood-altering magic. Nature, 566(7742), S8–S9. https://doi.org/10.1038/d41586-019-00398-1
Temple, J. L., Bernard, C., Lipshultz, S. E., Czachor, J. D., Westphal, J. A., & Mestre, M. A. (2017). The Safety of Ingested Caffeine: A Comprehensive Review. Frontiers in psychiatry, 8, 80. https://doi.org/10.3389/fpsyt.2017.00080
O’Callaghan, F., Muurlink, O., & Reid, N. (2018). Effects of caffeine on sleep quality and daytime functioning. Risk management and healthcare policy, 11, 263–271. https://doi.org/10.2147/RMHP.S156404
Delimont, N. M., Haub, M. D., & Lindshield, B. L. (2017). The Impact of Tannin Consumption on Iron Bioavailability and Status: A Narrative Review. Current developments in nutrition, 1(2), 1–12. https://doi.org/10.3945/cdn.116.000042
Korkmaz, S., Yıldız, S., Korucu, T., Gundogan, B., Sunbul, Z. E., Korkmaz, H., & Atmaca, M. (2015). Frequency of anemia in chronic psychiatry patients. Neuropsychiatric disease and treatment, 11, 2737–2741. https://doi.org/10.2147/NDT.S91581
Vulser, H., Wiernik, E., Hoertel, N., Thomas, F., Pannier, B., Czernichow, S., Hanon, O., Simon, T., Simon, J. M., Danchin, N., Limosin, F., & Lemogne, C. (2016). Association between depression and anemia in otherwise healthy adults. Acta psychiatrica Scandinavica, 134(2), 150–160. https://doi.org/10.1111/acps.12595
Hussain, G., Huang, J., Rasul, A., Anwar, H., Imran, A., Maqbool, J., Razzaq, A., Aziz, N., Makhdoom, E. U. H., Konuk, M., & Sun, T. (2019). Putative Roles of Plant-Derived Tannins in Neurodegenerative and Neuropsychiatry Disorders: An Updated Review. Molecules (Basel, Switzerland), 24(12), 2213. https://doi.org/10.3390/molecules24122213
Chin, J. M., Merves, M. L., Goldberger, B. A., Sampson-Cone, A., & Cone, E. J. (2008). Caffeine content of brewed teas. Journal of analytical toxicology, 32(8), 702–704. https://doi.org/10.1093/jat/32.8.702
Willson C. (2018). The clinical toxicology of caffeine: A review and case study. Toxicology reports, 5, 1140–1152. https://doi.org/10.1016/j.toxrep.2018.11.002
