Hintikka, J., Tolmunen, T., Honkalampi, K. et al. Eur J Epidemiol (2005) 20: 359. doi:10.1007/s10654-005-0148-2
Tea drinking has been suggested to be beneficial in neurodegenerative diseases where depressive mood is a common symptom. Nevertheless, it is not known whether there are any associations between tea drinking and depression in general populations. In this study we investigated these associations in a sample of the Finnish general population (n = 2011) using a postal questionnaire and the Beck Depression Inventory (BDI). Those who reported drinking tea daily were less depressed than the others. They had a lower mean BDI score and also a lower prevalence of depression. None of those whose daily tea intake was five cups or more had depression. Several potential confounding factors were included in the final sex- and age-adjusted multivariate logistic regression model which suggested that those who drink tea daily may have a significantly reduced risk of being depressed (adjusted odds ratio 0.47, 95 confidence interval 0.27–0.83). In conclusion, an inverse relationship between daily tea drinking and the risk of being depressed was found in a relatively large general population sample. Nevertheless, the underlying mechanisms are unresolved and further studies are needed.