Kate Morland, Nutritionist
Green tea is rich in antioxidants which are needed to protect our bodies against the effects of free radical damage.
Tea is one of the leading beverages consumed worldwide (1). It comes in many forms and flavours, but is there more to tea than meets the eye?
Our bodies are exposed to many pollutants from our environment, the food we eat and the lifestyle habits we may indulge in. These pollutants, among other things, are thought to cause our bodies to produce free radicals. Free radicals are nasty little molecules that damage our healthy cells leading to natural ageing and making us more susceptible to disease.
Antioxidants are molecules that roam our body like “pac-man”, engulfing or neutralising reactive free radicals that try to destroy our body cells. Antioxidants support many functions of the body especially our immune, digestive and detoxifying systems. Unfortunately antioxidants have a short life span and can act on only a single free radical. Therefore we must re-supply our tanks with antioxidant rich foods such as fruit, veggies and tea.
Tea, whether its black, green or white, contains antioxidants called flavonoids. Green tea comes from the same plant as black and white tea, Camellia Sinensis(2). However due to growing methods, manufacturing and preparation, green tea contains a higher amount of the flavonoids called catechins. Catechins have been highly researched and there is promising evidence to support their role in reducing the risk of major health problems (2).
Green tea does contain naturally occurring caffeine however the amount is less than black and white tea. The amount of caffeine in green tea will depend on ratio of water to tea leaf, how long the leaves are steeped and the quality of the tea.
A typical amount of caffeine in beverages(3):
(1) Conrad Astill,* Mark R. Birch, Clive Dacombe, Philip G. Humphrey, and Philip T. MartinJ. Factors Affecting the Caffeine and Polyphenol Contents of Black and Green Tea Infusions Agric. Food Chem. 2001, 49, 5340-5347 (2) Sabu M Chacko,1 Priya T Thambi,1 Ramadasan Kuttan,2 and Ikuo Nishigaki1. Beneficial effects of green tea: A literature review. Chin Med. 2010; 5: 13.(3) Adapted from USDA National Nutrient Database for Standard Reference, 2009; Center for Science in the Public Interest, 2007; Journal of Analytical Toxicology, 2008 http://www.mayoclinic.com/health/caffeine/AN01211.
Monday, 29 October 2012
Tuesday, 28 August 2012