What You Should Know About Green Tea
Did you know that tea comes second only to water as the most consumed drink in the world? Indeed, it appears that every second, 15 000 cups of tea are consumed! Black tea is generally more popular in the Western world, but green tea has particular properties that make it a must for all those who wish to optimize their health.
First of all, green tea is the kind of tea that has to go through the least amount of transformation. Its manufacturing processes allow us to avoid the fermentation (oxidization) of its polyphenolic compounds, and therefore to preserve their state within the leaf. These molecules, called catechins, are responsible for the plant’s cancer-fighting properties (Camellia sinensis). Recent studies suggest a beneficial effect for the prevention of prostate and bladder cancers. Polyphenols are said to reduce angiogenesis (the formation of new blood vessels to irrigate the tumours).
In addition to their preventive effect on cancer, the presence of both catechins and caffeine at the same time in a single beverage has a synergistic effect that contributes to increase energy expenditure by using more fat stored in fat tissues. In other words, green tea promotes weight loss.
There are different varieties of green teas, of which the composition can vary according to the time and place of the harvest, the various plants used, and the manufacturing process, all of which can influence the aroma as well as the caffeine and catechins content. For example, Gyokuro tea is a Japanese tea cultivated during the first harvests, which makes it milder and gives it one of the highest catechins content (Epigallocatechin gallate).
The advice of Richard Béliveau, Ph.D:
“To maximize the protection offered by tea, choose Japanese green teas as much as possible, which contain more cancer-fighting molecules, and leave your tea to brew at least 8 to 10 minutes to allow for a proper extraction of the molecules. Always drink freshly brewed tea, and drink your three cups over the course of the whole day.”
1- BÉLIVEAU, R. (2005). Les aliments contre le cancer. Éditions du Trécarré (214p.).
2- DULLOO, A and al., (1999). Efficacies of a green tea extract rich in catechin polyphenols and caffeine in increasing 24-h energy expenditure and fat oxidation in humans. The American Journal of Clinical Nutrition. No 70. P.1040-1045.
By Audrey-Ann Lemay, nutrition intern.