Green tea comes from the leaves of the flowering plant Camellia Sinensis, which is native to China, South and South-East Asia. References to green tea in Chinese literature date back some 5000 years and its world wide consumption is second only to water. The purpose of this article is to explore the magical health benefits of this drink, which has been dubbed 'The Elixir Of Life' and to compile the scientific evidence which elevates these benefits from myth to reality.
Legend has it that green tea was first discovered by Emperor Shen Nung, who has become known in Chinese mythology as the 'divine farmer' and is credited with bringing agriculture to Ancient China. The legend goes, that whilst drinking a cup of hot water Shen Nung noticed a floating tea blossom which landed in his drink, impressed with the taste Shen Nung decided to experiment further with his new discovery and was soon remarking on the many health benefits of green tea, which included curing abscesses around the head, helping with bladder and lung infections, lessening the desire for sleep, cheering the heart and quenching thirst. However it wasn't until sometime around the 8th century AD during the Tang Dynasty, that green tea finally got the credit it deserved, in China at least. This was thanks to the young scholar Lu Yu, who after many years of studying teas and herbs, finally wrote a book called Cha Jing or 'Tea Classic'. The book directed the reader in the art of tea brewing and drinking and finally brought the many benefits of drinking green tea to the masses. Eventually in the 9th century AD green tea made its way to Japan, where famous teas such as Matcha, Sencha and Bancha were developed. Finally in the 1600's tea reached the continent of Europe, but it wouldn't be until some 300 or so years later, in the 1970's that the Western World would finally realise the powerful health benefits of this some what modest herb.
In 1211 the Japanese monk Eisai wrote: 'Tea is a miraculous medicine for the maintenance of health. Tea has an extraordinary power to prolong life'...In fact research suggests that drinking 5-6 cups of green tea a day increases longevity by up to 16% and can slow cognitive decline. Cognitive decline is associated with ageing and is characterised by increasing difficulities in new learning, information processing and language. Since maintaining proper cognitive function is absolutely paramount to prolonging life, then green tea should be the number 1 priority on your shopping list! A study carried out on cognitive decline at Erasmus Medical School, Rotterdam, The Netherlands, by DJ Deeg, A Hofman and RJ Van Zonneveld, found: 'The rate of decline in cognitive function was strongly associated with subsequent survival time in the ages 70 years and over, with those with a large decline having a short survival time...' In a recent study into preventing neurological conditions such as Alzheimers, Parkinsons and Multiple Sclerosis, Dr Douglas Kell of Manchester University U.K found that nutrients in green tea, as well as darkly coloured fruit and veg, held the natural secret to warding off these debilitating illnesses.
In Ancient times the many health benefits of green tea were said to be the result of the magical properties of the tea leaves and in modern times science can put a name to this magic...polyphenols. Polyphenols are a large family of natural compounds found in plant organisms, there are various classes of polyphenols and most food stuffs contain complex mixtures of them. Most of the polyphenols that are common to our diets are not necessarily as active within our bodies as the polyphenols from green tea. This is because they have lower intrinsic activity or because they are poorly absorbed from the intestine, highly metabolised or rapidly eliminated. These super compounds are also found in blueberries, spinach, soybeans and peanuts among others, but levels simply don't compare with those in green tea and they aren't as bioavailable.
The polyphenols in green tea are antioxidants that have been found to 'neutralise' the free radicals in our bodies. Basically environmental pollutants such as cigarette smoke, auto exhaust fumes, pesticides, ultra-violet rays and even oxygen contain highly reactive, unstable molecules known as 'free radicals'. These unstable molecules race around the body looking for electrons in order to stabilise themselves. They do this by stealing an electron from another stable molecule, which in turn must go off and 'scavenge' an electron from another molecule and so a chain reaction begins! Eventually this results in damage to cells, tissues, organs and even DNA. Free radicals contribute significantly to the ageing process and may be a major factor in cancer and heart disease. A class of polyphenols in green tea known as catechins donate an electron to these free radical molecules, preventing them from stealing and ensuring a 'calm' environment within the body.
The catechins in green tea make up 30% of the dry weight of the tea and provide a whole host of health benefits. They can destroy powerful bacteria such as salmonella and cholera and may inhibit the actions of viruses like flu and even HIV. These catechins also reduce the risk factors associated with heart disease and stroke. The reduction in the risk of heart disease may be due to the ability of the catechins to lower cholesterol levels, improving the ratio of good (HDL) to bad cholesterol (LDL) and lowering triglyceride levels. In fact research shows that drinking 3 cups of green tea a day reduces the risk of heart attack by 11%. The catechins in green tea come in several forms, but in the form Epigallocatechin gallate (EGCG) they are pharmacologically most effective and 1 cup contains 180mg of EGCG, depending on the quality of the tea. The antioxidant effect of EGCG is 20 times as strong as that of vitamin E and has been shown to inhibit the growth of cancer cells, killing them off without harming any healthy tissue. Research shows that EGCG induces apoptosis or 'cell suicide', this is a sequence of events leading to the death of unhealthy or old cells, preventing any harmful substances from being released into the surrounding area. Science continues to prove more and more of these incredible benefits that are associated with the EGCG in green tea and relatively recent studies show they may have benefits in inflamation related conditions such as hepititis and arthritis.
Green tea extract is often one of the main components of weight loss products and it is the fat metabolising abilities of EGCG that makes it such an integral part of any fat burning complex. EGCG increases metabolism, reducing the storage of fat, as well as metabolising any stored fat to be used as energy. As part of a fat burning complex, green tea extract enhances the effects of any other thermogenics in the product, preventing the accumulation of fat. The combination of EGCG, caffiene and theobromine is vital for fat metabolism and may prolong and exaggerate the initial release of adrenaline normally associated with caffiene intake alone, the release of adrenaline results in a boost in energy metabolism and thermogenesis. It may be interesting to note that tests carried out have confirmed that EGCG is more effective than equivalent amounts of caffiene and ephedrine in activating thermogenesis. However when choosing a weight loss product containing green tea extract, make sure it is standarised to contain EGCG, otherwise it may be totally useless as a fat burner. Green tea, healthy diet and exercise can help reduce visceral fat by as much as 87%!...and 58% of this may be down to the green tea alone!...add to this the fact that drinking green tea can improve you endurance by up to 24% and the over whelming benefits of having this 'super' beverage in your daily diet should be apparent!
Vitamins in green tea?...The elixir of life is known to contain a higher concentration of vitamins than other food sources. It contains about 1 1/2 times more vitamin C than a red pepper, which has one of the highest concentrations amongst veg. 100g of green tea contains 1.4mg of vitamin B2 (Riboflavin), this is 4 times more than that of the super herb parsley. Riboflavin is important for metabolising energy and for the formation of red blood cells. It also aids glucose metabolism and there is a strong relationship between lean body mass and dietry riboflavin. 1-2% of the dry weight of green tea leaves is theanine, it is this amino acid that acts against the stimulating effects of caffiene on the central nervous system. It does this by stimulating the production of alpha brain waves, this creates a state of deep relaxation whilst maintaining a certain amount of mental alertness. Theanine also enhances levels of dopamine and reduces serotonin levels, which results in improved memory and learning ability, as well as playing an important role in regulating blood pressure. The presence of theanine in green tea is a significant factor in the teas ability to relieve stress and is a perfect alternative to anti-depressants which leave you sedated and drowsy.
The oral bioavailability of green tea may be quite low and research carried out and approved by University of Arizona Human Subjects Committee, found that consuming EGCG on an empty stomach after an overnight fast provided for greater oral bioavailability of catechins. There is also another theory that piperine, a black pepper alkaloid increases the bioavailability of EGCG. Apparently adding around 1.4g of black pepper to your brew will increase bioavailability...yes we have tried it!...and no, it don't taste too good!...bloody horrible infact!!
Chinese proverb - 'It is better to be deprived of food for 3 days than tea for 1' On this basis we at Monkey Nutrition believe it is important to drink between 3 and 5 cups of green tea everyday.