Wcardamom Green tea It has a long-standing reputation for health benefits, and research has been more mixed on black tea. Maki Inoue-choi, an epidemiologist at the National Cancer Institute, says one problem is that large observational studies on tea and mortality have focused on countries like Japan or China — places where green tea is most common.
To fill this gap, Inoue-Choi and colleagues analyzed the data in a file United kingdomWhere black tea is commonly drunk. After surveying nearly 500,000 people and following them for 11 years, the results were published August 29 in the journal Annals of internal medicineBlack tea gave a boost. Among the tea-drinking population—89% of whom drank black tea, compared to 7% of those who drank green tea—tea drinking was associated with a slightly lower risk of mortality for those who drank two or more cups a day compared to non-tea drinkers. People who added milk or sugar also experienced the benefit, and results remained consistent regardless of the tea temperature. The results also indicate that tea drinkers were less likely to die from cardiovascular disease, ischemic heart disease and stroke than those who did not drink tea.
While it’s hard to pin down why tea drinkers live longer, that’s not entirely surprising. According to Ino-choi, tea is “extremely rich in bioactive compounds” that reduce stress and inflammation, including polyphenols and flavonoids.
2020 study Which used the same British database as the new research found that there was an association between higher consumption of both black and green tea and biomarkers that predict cardiovascular health, including lower cholesterol levels. Research has also suggested that tea can help lower blood sugar blood pressure.
Going forward, researchers should take a closer look at the relationship between tea and cardiovascular disease, says Rob M. Van Dam, professor of exercise and nutrition sciences at George Washington University’s Milken Institute School of Public Health, who was not involved in the study. He notes that one of the surprising things about the new research is that there is no association between an increased dose of tea – the amount a person consumes – and a lower death rate after a person drinks two or three cups. The exception, he said, is if you exclude coffee drinkers, who may have made it difficult to determine the relationship between more tea drinking and mortality because they had lower mortality during the study. Without coffee drinkers, it became clear that drinking tea was linked to a lower risk of death from heart disease. “The association between tea consumption and cardiovascular mortality may be driving the association between tea consumption and all-cause mortality,” Van Damme says.
However, none of this means that you should run to your kettle. The new research is based on an observational study – which means that the evidence was not gathered from an experiment, and that the results were inferred by the researchers. Experts say the results should not be used to make health decisions, and should be replicated in randomized clinical trials. In addition, the magnitude of the association between tea drinking and mortality was modest, which means that it is possible that another trait of the tea drinkers led to this effect, Van Damme says. For example, people who drink tea may be less likely to consume Soft drinks.
As Inoue-Choi said, the new findings should be reassuring for people who drink tea regularly. But, she says, “people should not change the number of cups of tea they drink per day because of these findings.”
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