It also found that the humble cuppa could help strengthen bones, a finding that goes against earlier suggestions that tea's caffeine and fluoride may adversely affect bone health.
The full range of tea's restorative properties uncovered by the research is good news for our nation of tea-drinkers.
Other findings included that tea hydrated the body and improved alertness and mood levels.
For her study, Carrie Ruxton, a dietician and member of the independent Tea Advisory Panel, reviewed existing scientific literature on black tea, the type found in most teabags in Britain.
Clinical studies reveal that natural plant antioxidants found in tea, called polyphenols, have beneficial effects on many biochemical processes in the body.
The advantageous properties include reducing the risk of a heart attack.
Dr Ruxton said: "The clearest consistent evidence points to an association between tea consumption, in excess of three cups per day, and a reduced risk of myocardial infarction or a heart attack.
"This is good news for the many avid tea drinkers in Britain."
The researcher also found that the addition of milk made no change to the effectiveness of the polyphenols.
"My study also found emerging evidence that older women - those most at risk of brittle bones - had significant increases in bone density if they drank more than four cups of tea a day," Dr Ruxton said.
"It is clear that tea is worthy of further research and, in the meantime, can be enjoyed within the optimal intake range of 3 to 8 cups per day."
The Tea Advisory Panel commissioned literature review also revealed that alertness and mood elevation were improved by the modest amount of caffeine found in tea.
The optimal intake was up to eight cups a day, the equivalent of 400 milligrammes of caffeine.
Eight cups delivered the benefits of polyphenols without the adverse effects on sleep quality or hydration caused by too much caffeine.
Other health benefits associated with tea drinking included protection against tooth decay.
Tea is the second most popular drink in the world after water. It has been drunk here for 350 years and Britons drink 165 million cups a day.
The full research results are published in next month's British Nutrition Foundation's Nutrition Bulletin.