Is it healthier to drink tea or coffee? Both says the science! In fact, drinking at least 4 cups a day of green tea and 2 cups of coffee has been shown to protect health and ensure greater longevity even in the presence of type 2 diabetes, as evidenced by a recent scientific research, published in the journal BMJ Open Diabetes Research & Care by a Japanese team (Komorita et al, BMJ, Oct 2020).
We know from previous research that green tea provides valuable antioxidants and anti-inflammatory substances. Coffee is also a precious source of bioactive compounds, including caffeine, which, if in excess, can cause damage to the cardiovascular system but in the right quantities is beneficial, since it acts on insulin sensitivity by reducing the risk of type 2 diabetes. However, no research has ever been done on the benefits of a combined intake of green tea and coffee, especially in the case of type 2 diabetes. Therefore, the researchers analyzed the lifestyle and health data of nearly 5,000 Japanese, with an average age of 66, all diagnosed with type 2 diabetes and participating in The Fukuoka Diabetes Registry, a large study aimed at understanding the impact of medicines and lifestyle on the lives of people with type 2 diabetes. The volunteers were followed for a period of five years in which their habit of drinking green tea and coffee was assessed through a questionnaire and their state of health was determined through measurements of their body weight, blood pressure and blood tests. At the end of the five years, what emerged was that drinking tea or coffee separately reduced the risk of disease and increased longevity. In particular, a cup of green tea a day has been associated by scientists with a 15% reduction in developing diseases capable of shortening life expectancy. Two cups a day of green tea was associated with a reduction in developing diseases of nearly 30% and four or more cups a day with a reduction of 40%. As for coffee, a cup of coffee a day has been shown to reduce the risk of deteriorating health by 20% while two cups a day have been associated with a 40% reduction in mortality risk. But even more interesting results were seen in those who drank both coffee and green tea. For example, those who drank 2-3 cups of green tea per day and 2 cups of coffee had a 50% lower mortality risk while a combination of 4 or more cups of green tea per day and 2 cups of coffee reduced by 63% the risk of illnesses that may lower life expectancy.
In short, from today we have another reason to include green tea and coffee in our diet!