20 November 2012
After water, tea is the world’s most popular beverage and it leads the way in the field of mind-boggling statistics. It is estimated that each day around the world 750 million litres of tea are consumed and in Australia 22 million cups of tea are drunk. All of this tea drinking involves the 3000 varieties of tea that exist (excluding herbal teas) all of which are made from the Camellia sinensis plant. The varieties derive from the locations in which the plants are grown, some additives (like bergamot to make Earl Grey) and differences in processing. There are three basic varieties of tea: black, green and oolong. Approximately 76 per cent of tea made is black, 22 per cent is green and two per cent is oolong. Black tea is fermented, dried and rolled, and it is this pervasive drink which has been linked in new research to lowering risk of type 2 diabetes.
Tea has been linked in recent times to many healthy outcomes. It does contain caffeine but the most significant chemicals in tea are flavonoids. The highest concentration (690 mcg/ml) is found in brewed hot tea, instant tea has about 100 mcg/ml and iced tea has less again. The addition of milk may lower flavonoid content somewhat but it does not interfere with absorption, and you still get the benefits of tea if you drink it with milk. Many studies tell us that tea has a range of health-promoting effects including reducing your risk of developing Alzheimer’s Disease, lessening anxiety, reducing cancer risk, boosting blood flow to the heart, lowering blood pressure and improving elastic tissue content of skin. All of this evidence led researchers to examine data from Data Mining International on tea consumption in 50 countries, gathered in 2009.
The data showed that the biggest tea-consuming nation in the world is Ireland (2kg per capita per annum), followed closely by the United Kingdom and then Turkey. The lowest black tea drinkers are Mexico, Morocco, China, Brazil and South Korea. Analysis showed that black tea consumption did not affect other disease rates but did lower the risk of developing type 2 diabetes.
It is not as if the UK or Irish diet and lifestyle is inherently opposed to developing diabetes, so perhaps tea consumption does help prevent diabetes occurring. Population studies do not always translate directly to individuals but it is a promising sign. So, time for a cuppa?