A lot of the dietary advice that comes at us these days seems to ask us to forgo our favourite foods, or swallow more stuff we're not partial to. Like most of us, I like an easy life, which is why I'm always on the lookout for good news about foods and drinks which may actually be enjoyed. So this week, my eye was caught by a study just announced by American researchers which showed that tea can help boost the function of the immune system. Drinking tea was found to help immune-system cells attack foreign invaders, an effect which clearly has the potential to keep infections at bay. It seems that stepping up our intake of the nation's favourite cuppa might be just the right thing to do should we find ourselves with an infection brewing.
While downing a few mugs of tea at the first sign of a fevered brow or sore throat makes good sense, longer-term consumption seems to have more profound benefits for the body, too. Tea is rich in a bewildering concoction of substances including phenolic compounds (such as caffeic acid, quinic acid and gallic acid), polyphenols (such as catechin, epicatechin and epigallocatechin gallate), and flavonols (such as quercetin, kaempferol and rutin). Tea's constituents have been found to have the capacity to 'thin' the blood and also quell damage in the body caused by inflammation and disease-promoting entities called free radicals. This combination of effects should, in theory at least, afford some protection against the biggest killer in the West - heart disease.
Several studies have examined the relationship between tea-drinking and heart disease. While not all studies suggest benefit, most do. One study published earlier this year found that compared to individuals drinking no tea, individuals drinking six or more cups of tea a day had about half the risk of suffering from heart disease. Another study, published last year in The American Journal of Clinical Nutrition, found that drinking two or more cups of tea each day was associated with a 43 per cent reduced risk of having a heart attack. This study also showed that tea drinkers were 70 per cent less likely to die from a heart attack compared to never-consumers. More evidence for the heart-related benefits of tea has came from a study of heart-attack survivors. This research found that in the first few years following a heart attack, drinking two or more cups of tea a day appeared to reduce the risk of dying by about 40 per cent.
While drinking tea appears to be good for us, some moderation is probably warranted. Tea contains caffeine (about one third to one half the amount found in coffee), so at high intakes there is always the risk of effects signalling an excess of this stimulant in the system. Anxiety, heart palpitations and insomnia are the main symptoms to look out for. Other than that, it appears it is good news for the 70 per cent of the population who drink tea.