No proof drinking tea cuts risk of early death

“The wonder brew! Tea cuts early death risk”.

A headline published in the Daily Mail newspaper on 30 August claims: “Tea cuts early death risk”.

The article reports on a study conducted by the National Institutes of Health in the United States, published in the Annals of Internal Medicine, which explored the potential association between drinking black tea and lower mortality risk. However, the Daily Mail’s print headline is wrong to suggest that the study proved that tea is responsible for reducing mortality rates.

While the study did find that participants who drank two or more cups of tea a day were less likely to die of any cause, during the follow-up period, than those who did not, it did not prove a causal relationship between drinking tea and not suffering an early death.

Full Fact contacted the Daily Mail about this error, and the newspaper has now issued a correction, published in today’s newspaper. 

It reads: “A headline to an article in Tuesday’s paper said that drinking tea cuts the risk of an early death. Although a study found this could be the case— as the article correctly explained— it did not prove that there was a causal relationship.”

Study found tea ‘modestly associated’ with lower risk of death

The study in question involved 498,043 men and women in the UK aged between 40 and 69 who self-reported their tea consumption.

After a median follow-up period of about 11 years, those who drank two or more cups per day were found to have between 9% and 13% lower all-cause mortality risk than those who did not drink tea.

However, the study did not show that drinking tea was the reason for this lower mortality risk.

Study author Dr Maki Inoue-Choi is quoted in the Daily Mail as saying the study is “observational”, which means  it’s impossible to say whether tea drinking itself or other factors associated with a higher likelihood to drink tea were behind the lower mortality risk. 

Speaking about the study,  Professor of Preventive Medicine and Public Health at the Autonomous University of Madrid, Fernando Rodríguez Artalejo, told the Science Media Centre: “Like any observational epidemiological study, this one does not definitively establish that tea is the cause of the lower mortality of tea drinkers; this is because it cannot exclude that the lower mortality is due to other health factors associated with tea consumption (so-called “confounders”).”

The Mail’s article later qualifies that the study found “regular consumption could reduce the risk of an early death” (our emphasis) while a different headline on the online version of the article says “Why drinking TEA could help you live longer: People who enjoy two cuppas a day have 13% lower odds of an early grave”.

The online version also clarifies “the observational study cannot prove that tea was behind the lower mortality risk and not other lifestyle factors.” However, this is not included in the print article, which featured on page 3 of the newspaper.

Newspapers inaccurately claiming that studies have found causal relationships, when in fact they have only demonstrated correlation is a common problem.

We’ve recently written articles highlighting similar misreporting of studies about tea drinking and dementia, gum disease and mental health and sleep time and heart disease.

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