Tea is the most abundant liquid consumed after water world wild. Throughout the world green tea has been used as a health-enhancing drink for thousands of years. Green tea contains unique health-promoting components such as polyphenols particularly flavonoids (EGCG) and L-theanine. Like black tea, green tea is made from the dried leaves of the Camellia sinensis plant, native to Asia. Green tea differs from black tea because it is not fermented and therefore portions of active components remain undestroyed in green tea.
Green tea contains compounds known as polyphenols, which have been shown to possess significant antioxidant activity ( Frei and Higdon, 2003; Tachibana et al.,2004). The major anti-inflammatory and antioxidative polyphenol present in green tea is epigallocatechin gallate or EGCG. Evidence has shown EGCG to be 200x more potent than vitamin E in protecting the brain which is especially susceptible to free radical damage and oxidative stress (Frei and Higdon, 2003) . In addition green tea not only protects but has also been shown to stimulate the regeneration of damaged cells and tissues (Herniquez et al. 2002, Vinson et al 1995).
A 2011 meta-analysis showed green tea has a significant positive effect on weight loss and on weight maintenance. Green tea was found to increase energy expenditure and fatty oxidation. Specifically, EGCG treatment significantly reduces body weight especially in those with central or abdominal obesity (Chen et al. 2015).. The postulated mechanism by which is is achieved is ECGC is shown to decrease the secretion of ghrelin and increases adiponectin leading to reduced appetite and increased fat breakdown.
The heart and stroke society estimates 1.3 million Canadians are living with heart disease and up to 80% of these cases are preventable by adopting a healthy lifestyle (Koon et. al 2015). In fact, by adopting healthy behaviours, you can delay the onset of heart disease or stroke by as much as 14 years! I cannot think of a better reason to start transitioning towards health NOW.
A recent 2016 meta-analysis looked at 259,267 individuals and the results without a doubt showed drinking 1-3 cups of green tea per day lowers your risk of developing CVD, intracerebral hemorrhage, cerebral infarction, myocardial infarction and stroke (Pang et al. 2016). In addition green tea consumption was associated with a lower total all cause mortality rate!
Protection from Xenobiotics
Our environment has become poisoned with indiscriminate usage of synthetic chemicals, and pesticides leading to contamination of land, air and water with xenobiotics. Exposure to these toxins has become unavoidable and results in severe health effects. Green tea through its defensive actions has the ability to potentially neutralize the damage caused by these agents. Evidence suggests the polyphenols in green tea scavenge free radicals and reactive oxygen species through their hepatoprotective effects .
Green tea contains L-theanine, a derivative of glutamate, which has been shown to cross the blood-brain barrier and reduce stress by inhibiting cortical neural excitation and influencing the secretion of neurotransmitters in the brain. Specifically L-theanine increased the alpha-band frequency in the brain which indicates the mind is relaxed (Kakuda et. al 2000). However the caffeine content mitigates the sedative effects resulting in you being alert, focus but not drowsy.
The component EGCG has been scientifically shown to possess anti-inflammatory effects in the human brain. EGCG attenuates the inflammatory response and the results researchers provide possibility for its therapeutic application to neurodegenerative diseases such as Cognitive Decline, Alzheimer’s and Parkinson’s Disease (Kim et. al 2007, Weinreb et al 2004).
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