Regular tea consumption helps promote a “better organized” brain, claims study

13 Sep 2019 --- A recent study led by researchers from the National University of Singapore (NUS) suggests that regular tea drinkers have “better organized” brain regions – associated with healthy cognitive function – compared to non-tea drinkers. The research team made this discovery after examining neuroimaging data of 36 adults aged 60 and above, which revealed that those who consume tea at least four times a week have “better brain efficiency.”

“It is possible that certain varieties of tea are more efficacious [in promoting ‘organized’ brain regions], but we do not have sufficient number of subjects to test this hypothesis,” team leader Assistant Professor Feng Lei, from the Department of Psychological Medicine at the NUS Yong Loo Lin School of Medicine, tells NutritionInsight.

The study’s results offer the first evidence of positive contribution of tea drinking to brain structure and suggest that drinking tea regularly has a protective effect against age-related decline in brain organization, says Feng.

“This study focused on how efficiently the brain is organized as a complex network, and we are not using any brain disease as the study outcome,” he explains. “However, based on my earlier research, regular tea consumption may help to prevent cognitive decline and dementia. Using data from both Singapore and China, we also showed that tea consumption is related to less depression.”

The research was carried out together with collaborators from the University of Essex and University of Cambridge, and the findings were published in scientific journal Aging.

Regular tea consumers have brain regions that are “interconnected in a more efficient way.”Benefits of regular tea intake
Past studies have demonstrated that tea intake is beneficial to human health, and the positive effects include mood improvement and mental decline prevention. The results of a longitudinal study led by Feng and published in 2017 reveal that daily consumption of tea can reduce the risk of cognitive decline in older persons by 50 percent.

Furthering their research in tea, the NUS scientists recorded data assessing the participants' health, lifestyle and psychological well-being. The elderly participants also underwent neuropsychological tests and magnetic resonance imaging (MRI). The study was carried out from 2015 to 2018.

Upon analysing the participants’ cognitive performance and imaging results, the research team found that individuals who consumed either green tea, oolong tea or black tea at least four times a week for about 25 years had brain regions that were “interconnected in a more efficient way.”

“Take the analogy of road traffic as an example – consider brain regions as destinations, while the connections between brain regions are roads. When a road system is better organizsed, the movement of vehicles and passengers is more efficient and uses less resources. Similarly, when the connections between brain regions are more structured, information processing can be performed more efficiently,” explains Assistant Professor Feng.

“Our current results relating to brain network indirectly support our previous findings by showing that the positive effects of regular tea drinking are the result of improved brain organization brought about by preventing disruption to interregional connections,” he adds.

Functional teas
As cognitive performance and brain organization are intricately related, the NUS researchers note that more research is needed to better understand how functions like memory emerge from brain circuits, and the possible interventions to better preserve cognition during the ageing process. Still, consumer interest in the benefits of tea continues to inspire NPD in the space of functional teas and tea extracts.

Last month, Canadian brand Wize Monkey created a tea product made from upcycled prunings of the arabica coffee plant, which offers high levels of antioxidants, vitamins, minerals and phenolic compounds. Based on compiled research, compounds in the coffee leaves were found to be beneficial in helping prevent cerebrovascular disease, promote anti-inflammatory activity, manage blood sugar levels and aid weight loss.

Similarly in May, Avocado Leaf Tea made its debut, marketed as offering a high concentration of polyphenols and flavonoids, delivering a drink that is high in antioxidants. The leaves are marketed as providing a “rich source of bioactive compounds,” in addition to functional nutrients such as minerals, vitamins, fatty acids, proteins, fibers and polyphenols.l

Capsulized tea compounds present a convenient mode of consumption for time-starved consumers. However, when taken as food supplements, green tea catechin – a type of phenolic compound found in tea, with high antioxidant activity – consumed at or above 800mg/day, was found to pose health concerns, according to a study by European Food Safety Authority (EFSA). The assessment follows Nordic reports of cases of liver damage, possibly associated with the use of green tea products.

When asked if regularly consuming antioxidant supplements present the same effects as regularly drinking tea, Assistant Professor Feng responds, “We need clinical trial data to prove or reject any claim on the efficacy of a certain type of supplement. We would need well designed trials for this purpose.”

By Benjamin Ferrer