Drinking 3 cups of tea daily could delay aging, study suggests

Key findings: Their research, published in The Lancet Regional Health – Western Pacific in November, found that people who drink tea everyday exhibit signs of slower biological aging, especially those who consume three cups. The study also found that drinkers are less likely to experience anxiety, insomnia and depressive symptoms.

The scientists attributed their findings to polyphenols, which are plant compounds that promote good gut microbiota and help regulate the immune system, metabolism and cognitive function. They also cited a previous study linking flavonoids — a type of polyphenols abundant in tea — for extending the life expectancy of organisms such as mice and worms.

How the study was conducted: The researchers analyzed data from 7,391 Chinese participants aged 30-79 from the China Multi-Ethnic Cohort Study and 5,998 British participants aged 37-73 from the U.K. Biobank. The participants were asked about their tea preferences — black, green or yellow — how frequently they drink and how many cups they consume. Biomarkers such as blood pressure, cholesterol and body fat were also assessed to determine their biological age.

Important note: The researchers said they could not conclude that the participants’ tea-drinking habits are directly responsible for delaying their biological age. “Causal conclusions should be interpreted prudently,” they said.

The big picture: Past studies found that tea, as well as coffee, could help reduce the risk of cognitive disorders such as dementia and Alzheimer’s disease when consumed moderately. Tea is also associated with providing mental alertness and improving dental health, notably for preventing plaque buildup and tooth decay due to its fluoride and tannin content.