Tea has likely been around for thousands of years, thought to have first been drunk by the Shen Nong Dynasty of China as a medicinal drink. Over time, it spread around Asia and across the world, with the Brits first getting their hands on a cuppa in the 17th century. Tea is purported to have all sorts of health benefits, from weight loss to improving mental wellbeing, although much of the evidence is weak. Now, a small study published in Aging suggests that a nice hot brew might have a beneficial effect on the structure of our brains.
An international team of scientists wanted to assess how regular tea drinking might affect the physical structure of our brains and how they’re wired up. They asked a group of volunteers to complete a questionnaire about their tea-drinking habits, stating how often they consumed different kinds of tea. The participants were then divided into two groups, regular tea drinkers and non-tea drinkers. They then underwent MRI scanning so that the researchers could get a look at their brains.
The tea aficionados appeared to have less hemispheric asymmetry in the structural connectivity network of their brains, ie brain connections were more evenly spread between the two sides of the brain. Greater asymmetry has previously been linked to aging in the brain.
Meanwhile, the tea drinkers seemed to have stronger connections in the default mode network of their brains, an area of interacting brain regions involved in a variety of processes, like planning for the future and thinking about others.
The researchers say that their findings suggest drinking tea improves brain structure to make the brain more efficient, and may even slow the effects of aging on the brain, but before you stick the kettle on, there are some caveats to take note of.
First, the study used a very small number of participants; 15 tea drinkers and 21 non-tea drinkers. This sample size is simply too small to draw concrete conclusions, so much more research is needed to back the findings up. Meanwhile, all participants were over 60, and only 16 percent were male, so it is difficult to apply the findings to the wider population.
As Medical News Today points out, a propensity to drink lots of tea could be linked to other factors that affect the brain. For example, highly sociable people might drink more tea when hanging out with friends and family, and this sociability could have a positive effect on brain structure.
While regular tea drinking certainly won't hurt you, we need more robust studies to truly conclude what its benefits might be. It seems this pot of research needs a little more time to brew.