We are well aware that coffee contains caffeine and is a rich source of antioxidants and other bioactive compounds. And we know that tea containing caffeine, catechin polyphenols and flavonoids has also been reported to play neuroprotective roles such as antioxidative stress and anti-inflammation.
While previous studies have revealed the involvement of coffee and tea in the development of stroke and dementia, little is known about the association between the combination of coffee and tea and the risk of stroke, dementia, and post-stroke dementia.
Aiming to investigate the associations of coffee and tea separately as well as in combination, researchers from Tianjin Medical University have studied healthy individuals aged 50-74 from the UK BioBank.
Participants were recruited between 2006 and 2010 and followed until 2020. At the outset participants self-reported their coffee and tea intake. Over the study period, 5,079 participants developed dementia and 10,053 experienced at least one stroke.
People who drank 2-3 cups of coffee or 3-5 cups of tea per day, or a combination of 4-6 cups of coffee and tea had the lowest incidence of stroke or dementia.
Individuals who drank 2-3 cups of coffee and 2-3 cups of tea daily had a 32 percent lower risk of stroke and a 20 percent lower risk of dementia compared with those who drank neither coffee nor tea. Intake of coffee alone or in combination with tea was also associated with a lower risk of post-stroke dementia.
“We found that drinking coffee and tea separately or in combination were associated with lower risk of stroke and dementia,” the study’s authors concluded.
“Our findings support an association between moderate coffee and tea consumption and risk of stroke and dementia, however, whether the provision of such information can improve stroke and dementia outcomes remains to be determined.”
The UK BioBank reflects a relatively healthy sample in comparison to the general population which could restrict the ability to generalise these associations. While that may be the case, any research into the risks of stroke and dementia is positive in helping us understand these conditions and possibly help protect people from being affected in the future.
Strokes cause 10 percent of deaths globally and dementia is a global health concern that has a high social and economic burden.