Chemistry: Phytochemicals are the bioactive compounds which are present in medicinal plants. The bioactive constituents of the tea leaf include tea polyphenols (micronutrients with antioxidant properties), proteins and amino acids (especially L-theanine, an amino acid thought to be unique to tea), alkaloids (caffeine), vitamins (esp. Vitamin C and E, and niacin) and mineral compounds (esp. potassium).
Flavonoids are the largest family of polyphenols and the four most active flavanoids in tea are known as catechins and gallocatechins (EC, EGC, EC and EGCG). When these are enzymatically oxidized during tea processing they form other antioxidant polyphenols, theaflavins and thearubigins, and this differentiates unoxidised tea (white, green) from oxidised tea (black). While green tea is green because of chlorophyll from the leaves, black tea gets its reddish-yellow colour from these oxidised catechins. Antioxidants, as a group, help protect the cells in your body from free radical damage.
L-theanine, an amino acid constituent of tea, is now known to increase dopamine and seratonin production in the brain and has a convincing effects on anxiety and depression. It induces relaxation through the enhancement of alpha wave activity in the brain, without the fatigue effect, hence why tea is used for the relaxed state of alertness and concentration that it creates. Among other things, L-Theanine helps to protect neural damage and improve nerve function, serving as an anti-stress agent.
Caffeine and L-theanine are pharmacologically important constituents of tea, especially due to their effects on the central nervous system. The effects of these two compounds are opposite: While caffeine is a well-known stimulant, theanine has a relaxing effect.
L-theanine’s interaction with caffeine actually enhances performance in terms of attention switching and the ability to ignore distraction, while balancing the more acute effects of higher doses of caffeine.
Primary effects: A gentle balance between stimulant and relaxant, when drunk as a brew it creates a state of calm wakefulness. Mood lifting and harmonising, it warms body and soul.