If you're feeling a bit stressed out with life, have a good cup of tea to help you unwind, according to a team of UK scientists.A new study by University College London (UCL) researchers showed that drinking daily cups of black tea can help the relaxation process due to its effect on the body's stress hormone levels.

The de-stressing tonic
According to The effects of tea on psychophysiological stress responsivity and post-stress recovery: a randomised double-blind trial - the UCL study recently published in Britain's Journal of Psychopharmacology - people who drank black tea were able to de-stress quicker than those who drank a fake tea substitute.

The UCL researchers also found that blood platelet activation - linked to blood clotting and the risk of heart attacks - was lower in tea drinkers.

Six weeks, loads of tea and a group of young men
The study involved 75 young men who were split into two groups and monitored for six weeks. One group was given a tea drink mixture which had the ingredients of an average cup of black tea and the other group was given a fake drink without the active tea ingredients.

The groups' blood pressure, blood platelet, cortisol and self-rated stress levels were measured when they were exposed to one of three stressful situations - threat of unemployment, a shop-lifting accusation or an incident in a nursing home.

The results showed that even though there were similar stress levels in both groups, cortisol levels dropped by an average of 47 per cent in the tea drinking group compared with 27 per cent in the fake tea group, just 50 minutes after the task.

Tea-drinking tradition with results
Professor Andrew Steptoe from UCL's Department of Epidemiology and Public Health, said: "Drinking tea has traditionally been associated with stress relief, and many people believe that drinking tea helps them relax after facing the stresses of everyday life.

"Tea is chemically very complex, with many different ingredients. Ingredients such as catechins, polyphenols, flavonoids and amino acids have been found to have effects on neurotransmitters in the brain, but we cannot tell from this research which ones produced the differences.

"Nevertheless, our study suggests that drinking black tea may speed up our recovery from the daily stresses in life. Although it does not appear to reduce the actual levels of stress we experience, tea does seem to have a greater effect in bringing stress hormone levels back to normal."

Researching life science
The UCL study was partly funded by the Biotechnology and Biological Sciences Research Council (BBSRC), the UK funding agency for research in the life sciences.