Green Tea

HABITAT

It is native to East Asia, the Indian Subcontinent, and Southeast Asia, but it is today cultivated across the world in tropical and subtropical regions. It appears cultivated as a bush of about 2.5cm in the high areas of asia and china with a warm and humid climate.

INTRODUCTION

Green tea, also known as unoxidized tea, is made solely from the leaves of the Camellia sinensis plant. The use of tea leaves probably first originated in the southwest ‘area of China more than 3,000 years ago and was likely initially used by people just for chewing and eating, Over time, the use of leaves and buds from the tea tree gradually expanded as people began to use in cooking and when added to boiling water to flavour the water they drunk.

BENEFITS

Enhances Brain Functioning: Green tea can help in improving brain functioning in addition to keeping you alert. Caffeine, a well-known stimulant, is the main active ingredient. It can block a chemical messenger in the brain called adenosine, which controls when you feel sleepy or awake. Blocking adenosine can prevent drowsiness, stay awake and mentally sharp. Green tea also contains an amino acid called L-theanine, which has been found to help reduce stress and boost your mood, which can also improve brain function when combined with caffeine by strengthening working memory and attention and reducing anxiety.

Lowers Cholesterol: Catechin is a major component of green tea. Catechins are natural antioxidants that have antioxidative, anti-inflammatory, and anti-hypertensive effects. They lower cholesterol levels by decreasing the absorption of cholesterol into the body.

Ayurvedic view: High cholesterol is a result of an imbalance in Pachak Agni (digestive fire). Impaired digestion at the tissue level produces excess waste products or Ama (toxic remains in the body due to improper digestion). This causes an accumulation of bad cholesterol. Green Tea helps in controlling High cholesterol by reducing Ama because of its Deepan (appetizer) and Pachan (digestive) properties. It also helps to remove blockage from the blood vessels by eliminating toxins. These properties together help reduce High cholesterol.

Keeps Heart Healthy: Green tea has been found to play a role in heart health by reducing the risk factors that cause heart disease. High blood pressure is one of the most common risk factors for heart disease. The flavonoids present in Green Tea reduce blood pressure by making nitric oxide more available in the blood. Nitric oxide relaxes narrowed blood vessels and lowers blood pressure. It also increases the blood flow by opening the blockage in the arteries due to its anti-inflammatory property. This helps prevent clogging of the arteries.

Helps In Burning Fat: Green Tea is a good beverage for weight loss and weight maintenance as it is a low-calorie drink. It is rich in catechins that increase metabolism and fat breakdown and inhibit lipid absorption.

Ayurvedic view: Green Tea has Deepan (appetizer) and Pachan (digestive) properties that help improve the digestive system and aid in weight loss.

Good for Skin Health: The antioxidant properties of Green Tea can be beneficial for the skin. It can avoid premature aging and fight off skin wrinkles. It contains certain constituents which can decrease the damaging effects of ultraviolet radiation on the skin.

Ayurvedic view: Due to its Kshaya (astringent) properties, it helps in maintaining the elasticity and firmness of the skin.

Improves Oral Health: Green Tea can help improve oral health. Certain constituents present in green tea may limit the growth of bacteria in the mouth, reducing the risk of bad breath. It also helps to control bleeding, reduce inflammation, and prevent bone resorption.

MECHANISM OF ACTION

Catechins are the antioxidant compounds that help destroy free radicals and reduce inflammation. They also have thermogenic effect that is they increase body temperature, which by activating metabolism and increasing energy expenditure leads to burning of body fat. Green tea is also high in a compound known as L-theanine that promotes a sort of 'calm relaxation', helps with focus, centring thoughts, and relaxation. It crosses the brain blood brain barrier where calls turn it into a chemical called GABA that helps the brain relax, but at the same time, caffeine will increase awareness. This prevents a caffeine crash, while allowing prolonged periods of concentration. Caffeine affects the brain by inhibiting an inhibitory neurotransmitter known as adenosine. This increases neuronal firing and neurotransmitter concentrations such as dopamine and norepinephrine. Antioxidants prevent damage in the cells and molecules within the body by suppressing the production of free radicals which cause the damage and speed up the aging process.

CLINICAL STUDIES & REFERENCES

Dulloo Ag, Duret C, Rohrer D, Girardier L, Mensi N, Fathi M, Chantre P, Vandermander J. Efficacy of A Green Tea Extract Rich in Catechin Polyphenols And Caffeine In Increasing 24-H Energy Expenditure And Fat Oxidation In Humans. 2000 Nov, Am J Clin Nutr., Vol. 72(5), Pp. 1232-4.
Sayama K, Lin S, Zheng G, Oguni I.Effects Of Green Tea On Growth, Food Utilization And Lipid Metabolism In Mice. Jul-Aug, S.L.: In Vivo. 2000; Vol. 14(4), Pp. 481-4.
Jj. Choo. Green Tea Reduces Body Fat Accretion Caused by High-Fat Diet in Rats Through Beta-Adrenoceptor Activation of Thermogenesis In Brown Adipose Tissue. 2003 Nov, S.L.: J Nutr Biochem., Vol. 14(11), Pp. 671-6.
Unno K, Noda S, Kawasaki Y, et al. Ingestion of Green Tea with lowered caffeine improves sleep quality of the elderly via suppression of stress. J Clin Biochem Nutr.;61(3):210-216.
Reto M, Almeida C, Rocha J, et al. Green Tea (Camellia Sinensis): Hypocholesterolemic effects in humans and anti-inflammatory effects in animals.FNS.2014;5:2185-2194.