Polyphenols found in green tea include epigallocatechin gallate (EGCG), epicatechin gallate, epicatechins and flavanols, which are under laboratory research for their potential effects in vivo. Other components include three kinds of flavonoids, known as kaempferol, quercetin, and myricetin. Although the mean content of flavonoids and catechins in a cup of green tea is higher than that in the same volume of other food and drink items that are traditionally considered to promote health, flavonoids and catechins have no proven biological effect in humans.
Rooibos grades are largely related to the percentage "needle" or leaf to stem content in the mix. A higher leaf content results in a darker liquor, richer flavour and less "dusty" aftertaste. The high-grade rooibos is exported and does not reach local markets, with major consumers being the EU, particularly Germany, where it is used in creating flavoured blends for loose-leaf tea markets.
Studies in laboratory animals have found that green tea polyphenols inhibit the growth of esophageal cancer cells (in line with its anti-cancer properties). Other clinical studies have found that green tea offers protection against the development of esophageal cancer, particularly among women. However, one large-scale population-based clinical study found just the opposite: drinking green tea was associated with an increased risk of esophageal cancer, and the stronger and hotter the tea, the greater the risk. It seems that if the water is very hot, it can damage the esophagus and lead to long-term adverse consequences. So just make sure the tea you drink isn’t extremely hot.
Green, black, brown and now, red! No, these aren’t just some colors on the palette of your paint box. They are hues in the world of tea. The latest addiction and addition to the list being the 'red' tea, all the way from South Africa. We are talking about the Rooibos tea. What makes Rooibos tea so popular is the fact that it is known to have 50% more antioxidants than those found in green tea. Rooibos is obtained from Aspalathus Linearis, a shrub native to the Cape of Good Hope.