A cuppa, a brew, char, Rosie Lee – your favourite tipple has lots of names, but is it healthy for you?
The drink that we call tea is actually black tea. Green and black tea come from the same plant, Camellia sinensis. Green tea is produced by lightly steaming the fresh-cut leaf, which prevents oxidation. With black tea, the leaves are left to oxidise. Green tea, therefore, has higher levels of antioxidants and, therefore, therapeutic activity.
Tea has been used as a beverage for nearly 5000 years. It was first consumed by the Chinese and was brought to Europe as explorers began to visit Asia. The first samples of tea reached England in the 1650s. It rapidly became popular enough to replace ale as the national drink! Tea importation rose from 18,000kg in 1699 to 110,000kg in 1708. In 1908, Thomas Sullivan, a tea-merchant from New York, developed the concept of bagged tea, to avoid the mess of tea leaves. Tea is the most popular beverage in the UK with over 100 million cups drunk every single day!
Both green and black tea contain relatively high amounts of vitamins C, K and B2. It also contains calcium, magnesium, zinc and nickel. A cup of tea contains only 1 calorie.
Regularly drinking tea may have health benefits such as decreasing the risk of chronic disease, improving gut health, reducing blood pressure and improving focus.
Green tea provides significantly more health benefits than black tea due its higher content of polyphenols (plant compounds). These compounds have antioxidant action, and are associated with lower rates of breast and prostate cancer.
Both green and black tea contain small amounts of caffeine. Caffeine is a stimulant, and is best avoided after noon as it may interfere with your sleep. Too much caffeine may also be a factor in heartburn as it may relax the cardiac sphincter (the valve at the top of the stomach).
Tea is also a source of oxalates, so people with a history of oxalate-containing kidney stones should also drink tea only in moderation. A further point is that tea can interfere with the absorption of iron, so if you are low in iron, it is best to drink your tea at a different time to eating iron-rich foods or supplements.