An apple a day may keep the doctors away, but tea could stave off dementia, a National University of Singapore (NUS) study has found.
Regular tea drinkers are less likely to get dementia compared with those who do not drink tea at all, and all that is needed is around 200ml, or the average kopitiam cuppa, once a day.
Tea can also help those whose genetics predispose them to getting Alzheimer's disease - the most common form of dementia - keep the disease at bay.
Whether the tea is green, black or oolong makes no significant difference, said Assistant Professor Feng Lei, who conducted the study.
However, the results, published last year, apply only to tea brewed with leaves from the tea plant - formally known as Camellia sinensis - and not to fruit or flower teas. And adding milk to tea will reduce the absorption of one of the chemicals called catechin.
Prof Feng, who is from the Yong Loo Lin School of Medicine's psychological medicine department, studied nearly 1,000 Singaporean Chinese seniors over a seven-year period.
Tea drinkers can lower their risk of cognitive damage by this amount.
Those who carry the ApoE4 gene, which carries a raised risk of getting Alzheimer's disease, can reduce that risk by this amount.
Prof Feng's team asked the seniors about their tea-drinking habits between 2003 and 2005, then followed up with them every two years between 2006 and 2010.
He found that people who made tea drinking a habit had a 61 per cent lower risk of having cognitive impairment, compared with those who did not drink tea.
The study also found that the 177 seniors with a gene known as ApoE4 - which can increase a person's risk of getting Alzheimer's disease by several times - had an 86 per cent lower risk of developing this problem if they were tea drinkers.
Although the study was conducted among Chinese, its results should apply to other ethnicities as well, Prof Feng said.
"The biology of how the brain changes during the ageing process and the compounds from tea are all the same, so I don't think there will be a difference," he said.
Dementia affects an estimated one in 10 people aged over 60 in Singapore, where the population of people aged 65 and above is expected to double to 900,000 by 2030.
Prof Feng said that tea leaves contain chemicals with anti-inflammatory and antioxidant properties, which could help to protect the brain. "Our understanding of the detailed biological mechanisms is still very limited, so we do need more research to find out definitive answers," he added.
The study results are good news to 28-year-old Jonathan Lim, who enjoys the hot beverage. "I drink green tea almost on a daily basis, so that's good to hear," said the civil servant.
An Italian study in 2012 found that consuming a cocoa drink every day could also keep dementia at bay.