We do love a good cup of tea in the UK. According to the Tea Council, we drink 65 million cups daily, and it is often said rather jokily that tea cures all ills, physically and emotionally! But even in the scientific literature tea, and particularly green tea, has been studied with regards to its potential health benefits, like heart health. The associations with health are thought to be due to the bioactive compounds in tea leaves known as polyphenols, (particularly a type known as catechins), suggested to have antioxidant properties as well improving vascular health (benefitting our blood vessels and therefore blood circulation). However, although the evidence on tea is promising, future research is necessary to fully understand its contribution to health.
Study looks at whether tea drinking may help prevent cognitive disorders
Recently a new study was published suggesting tea drinking could reduce the incidence of neurocognitive disorders (NCD). This longitudinal study looked at whether there was any association between tea drinking in 957 community-living Chinese older people (over 55s), and cognitive decline or dementia. Tea consumption information was collected from the participants from 2003 to 2005, and at regular intervals of two years, they were assessed on their cognitive function using the Mini-Mental State Examination score, as well as the Clinical Dementia Rating scale until 2010.
The researchers reported that regular tea drinkers had higher cognitive scores and a lower risk of neurocognitive disease particularly in carriers of the APOE e4 gene carriers who are genetically at greater risk of developing Alzheimer’s disease. Reduced NCD risk was observed for both black tea (the more commonly drunk in the UK like Ceylon, English Breakfast, Assam), as well as green and oolong tea. In fact, all these teas come from the same plant Camellia sinensis but are classified differently based on the level of oxidation or processing.
It’s too early to conclude that tea drinking is directly linked to better brain health
Whilst some of the properties of the compounds found in tea indicate they may have a role in protecting the brain, our understanding of the biological mechanisms is still very limited so we do need more research to find definitive answers. It’s certainly too early to conclude that tea drinking is directly linked to better brain health. This was a study carried out in an older Chinese population and although the study attempted to adjust for confounding factors like smoking, alcohol intake and physical activity, it’s difficult to discount the possibility that tea drinkers simply may have some other lifestyle, behaviour or other factors that may be influencing their cognitive health.
As an inexpensive, popular drink, a daily cuppa would be a wonderfully simple lifestyle measure if it could reduce a person’s risk of developing neurocognitive disorders in later life. But we do not know whether it can. So far the body of research as a whole is inconclusive. Additionally, tea drinking alone will never come close to the far stronger health promoter—a healthy and balanced diet and lifestyle.
Tea is a great fluid provider
As a nation of tea-lovers, the good news is that tea is a good source of hydration and an important fluid provider in the care home population. So let’s keep drinking it, but with the understanding that on current evidence, it is unlikely to have a dramatic impact on our risk of dementia.