A mug of the nation's favourite hot beverage helps fight off cancer, boosts the immune system, beats Alzheimer's and combats heart disease and diabetes, say nutritionists - including a Leeds academic.
The brew's superpowers stem from a secret ingredient called flavonoids.
They are naturally occurring compounds that act like antioxidants, destroying illness - triggering 'free radicals'.
As a further boost, tea is the only food with an amino acid called L-theanine known to improve mental focus and sleep quality.
Two to four cups a day provide the best results - with few additional benefits with higher intakes, a medical conference was told.
Professor Louise Dye, of the University of Leeds, said trials have found tea is also good for cognitive function - owing to a unique combination of caffeine and L-theanine.
Speaking at the Symposium medical conference, she said: "There is strong evidence that tea and its constituents seem to be beneficial under conditions of stress.
"The most profound cognitive domain that tea seems to act upon is attention and alertness.
"With these effects on attention, tea is an optimal beverage of choice during a time of elevated stress and burnout worldwide."
Symposium chairman Professor Jeffrey Blumberg, of Tufts University in Boston, said: "There is a growing body of research from around the world demonstrating that drinking tea can enhance human health in many ways.
"True teas - which include black, green, white, oolong, and dark - can contribute significantly to the promotion of public health.
"Evidence presented at this symposium reveals results - ranging from suggestive to compelling - about the benefits of tea on cancer, cardiometabolic disease, cognitive performance and immune function."
Green tea, for instance, contains natural antioxidants known as catechins that prevent cell damage, strengthen the immune system and enhance tissue repair.
Dr Dayong Wu, also from Tufts, said: "Tea may help support your immune system and increase your body’s resistance to illnesses.
"In the event you do become sick, tea can help your body respond to illness in a more efficient way by ridding itself of the infection and may also alleviate its severity when they happen."
It is estimated up to half of dementia cases could be prevented through changes in lifestyle - such as drinking more tea.
Professor Jonathan Hodgson, of Edith Cowan University in Perth, said: "There's growing evidence as little as one-to-two cups daily could significantly reduce risk of vascular dementia and potentially Alzheimer's disease."
Data also suggests higher intakes protect against cancers of the breast, womb, gallbladder, liver and mouth by dampening inflammation and boosting gut bacteria.
Dr Raul Zamora-Ros, of the Catalan Institute of Oncology in Barcelona, said: "While more research needs to be done to determine the exact dosage, the conclusion we can share is higher intakes of tea consumptions may reduce the risk of some forms of cancer."
Two cups of unsweetened tea a day has also been linked with staving off diabetes and heart disease - the world's number one killer.
One extensive review demonstrated each cup reduced the risk of a stroke or death from cardiovascular disease by four per cent, heart attacks by two per cent and all-cause mortality by 1.5 per cent.
Professor Taylor Wallace, of George Mason University in Virginia, said: "When you look at all the different biomarkers and mechanisms that tea is affecting, this bountiful beverage is one which consumers can easily add to better their diet and create a healthier and longer life for themselves."
The virtual meeting, organised by the Tea Council of the US, was told clearer recommendations are needed to support the growing evidence.
Prof Mario Feruzzi, of Arkansas University, said: "There may be other herbals and botanical products that can deliver health benefits but none of them are as systematically studied as Camellia sinensis - true tea.
"With true teas - white, green, black and oolong - you're dealing with thousands of years of traditional use, 60-70 years of systematic study which, in the last 15-20 years, has ramped up to the point where we have very definitive data."
Tea is by far the most popular drink consumed in Britain with over 100 million cups down every day - around 36 billion a year.