Tea is an aromatic beverage commonly prepared by pouring hot or boiling water over cured leaves of the Camellia Sinensis, an evergreen shrub native to Asia. As green tea and black tea are the most commonly used varieties of tea their advantages and side effects must be very well known.

• Green Tea is considered a dietary source of antioxidant nutrients as it is rich in polyphenols (catechins and gallic acid particularly) and phytochemical compounds. They may also function indirectly as antioxidants through :-
• Inhibition of redox sensitive transcription factors.
• Inhibition of ‘pro-oxidant’ enzymes, such as inducible nitric oxide synthase, lipoxyqenases, cyclooxygenases and Xanthine oxidase.
• Induction of antioxidant enzymes such as glutathione transferases and superoxide dismutases.
• The oxidation of LDL cholesterol, associated with a risk of artherosclerosis and heart disease is inhibited by green tea due to EC (Epicatechin) and EGCG (Epigallocatechin) antioxidant activity. Side effects of green tea may result by its excessive intake. It may lead to thyroid disfunctioning, muscle tremors, contractions, insomnia and allergies like eczema and hives.

Black Tea contains polyphenols such as thearubigins and theaflavins which are very powerful.

• It hydrates the body and strengthens the immune system with bacteria-fighting antioxidants and promotes blood flow to brain.
• It improves focus and concentration.

High amounts of black tea can cause side effects due its caffeine. These can range from mild to serious and include headache, nervousness, sleep problems, vomiting, diarrhoea, convulsions and confusion. It can be concluded that in comparison of black tea, green tea has much more health benefits but only if consumed in limited amount.