It is often said a cup of tea cures all ills. Now, a study has shown that the world's favourite hot beverage could be linked to a lower risk of mortality.
People in the UK who consumed two or more cups of black tea per day were found to have a significantly lower risk of death compared to non-tea drinkers, researchers said.
They found people who consumed the drink appeared to have a beneficial effect on mortality, regardless of whether participants also consumed coffee.
The effect still stood even when milk and sugar was added.
Previous studies suggested a modest inverse association for tea drinking and mortality, which has largely been seen in populations where green tea drinking is common, such as in China and Japan, wrote the authors of the study, which was published in the Annals of Internal Medicine.
“In contrast, published studies in populations where black tea drinking is more common are limited, with inconsistent findings.”
To address the gap, the authors investigated the association of tea consumption with mortality in Britain, where the consumption of black tea is common.
They examined a database containing the health records of about half a million people in the UK, collected over a four-year period between 2006 and 2010.
In total, 85 per cent of people involved in the study said they were tea drinkers, and of them, 89 per cent said they drank black tea.
Almost a third, 29 per cent, said they drank two to three cups a day, about a quarter said they drank four to five cups and 12 per cent said they drank six to seven cups.
“Relative to non — tea drinkers, participants who reported drinking two or more cups each day had a 9 per cent to 12 per cent lower risk for mortality,” the study said.
Among those who filled out a survey on how they took their tea, 74 per cent and 13 per cent of tea drinkers reported adding milk and sugar, respectively.
Tea drinking had a beneficial effect on mortality regardless of whether participants added milk and sugar, wrote the authors.
"Higher tea intake was associated with lower mortality risk among people who added milk," Dr. Maki Inoue-Choi, division of Cancer Epidemiology and Genetics, National Cancer Institute told The National.
"We saw a generally similar association among people who didn’t add milk up to 4-5 cups of tea per day. There are no association above that level, although fewer participants drank high amounts of tea without milk.
"The added amount of milk and sugar to tea on average is small and does not appear to alter the main finding that higher tea intake is associated with lower mortality risk. Nevertheless, we caution that dietary guidelines recommend avoiding large amounts of fat and added sugar."
The researchers said the findings of the study suggest tea drinking may be associated with “modestly lower mortality in a population in which black tea drinking is common”.
“The study cannot definitively prove that tea drinking directly reduced the risk for death during the follow-up period. However, these findings provide reassurance to tea drinkers and suggest that black tea can be part of a healthy diet.”
Tea is the most consumed drink in the world, after water, the UN Food and Agriculture Organisation reported.
In the UK, which is ranked third globally for tea consumption after Turkey and Ireland, about 100 million cups are drunk each day.
Black tea, which is made from the leaves of the Camellia sinensis bush, is stronger in flavour and contains more caffeine than other teas, but still less than coffee. It is also the world's most popular tea.
Its antioxidants and compounds could help reduce inflammation and blood pressure, lower bad cholesterol, and improve gut and heart health.
Previous studies have found it is linked to a reduced risk of stroke and dementia.
Researchers believe its properties may also help lower blood sugar following a meal or snack and reduce the risk of cancer.
It is thought antigens contained in the tea may even boost the immune response, helping to protect against illness.
However, studies have also linked tea and coffee consumption to an increased risk of oesophageal cancer.
It is believed hot drinks can destroy the inner lining of the oesophagus, causing the cells to continually regenerate, which creates a greater chance of errors that could turn cells cancerous.