When you drink green tea, it takes about 30 minutes for the full effect of the caffeine to take place and provide an energy boost. L-theanine is a natural amino acid that’s found in both green and black teas; although it is present in smaller amounts when compared with green teas, l-theanine provides a calming effect. L-theanine has been found to reduce any anxiety or jitters that may be brought on by drinking caffeine, and it also promotes a feeling of relaxation by acting on the alpha waves in the brain.
Green Tea is an herbal infusion from the Camellia sinensis plant, which has been consumed for more than 4,000 years. It contains caffeine and l-theanine, which are thought to account for its effects. The chemical content of green tea varies depending on its production and processing methods.
Green tea contains four types of polyphenols: flavonoids like catechin, epicatechin (EC), epicatechin gallate (ECG) and epigallocatechin gallate (EGCG); dimers like theaflavin; and monomers like thearubigin. Theaflavin is unique in that it is a type of polymerized tannins known as proanthocyanidins. Green tea also contains caffeine, a natural stimulant that temporarily increases alertness and reduces fatigue.
L-theanine is an amino acid found in green tea that provides a calm focus without drowsiness or anxiety, and thought to result in better sleep. Green tea is a popular beverage and is consumed daily in many parts of the world. Green tea provides antioxidants, which may reduce cellular damage caused by free radicals.
There are many green tea supplements available over the counter; these are not regulated as food and may contain harmful contaminants when produced cheaply. The U.S. Food and Drug Administration does not certify green teas as safe or effective for any medical use, nor does the US Food and Drug Administration regulate the quality or manufacturing of green teas. There is not enough evidence to support health claims related to weight loss, disease prevention, or any sort of treatment. That said, evidence is slowly piling up in favor of green tea. If you’re a regular green tea drinker, it might be useful to know where you get your green tea from, to ensure maximum benefits and minimal risk of side effects due to contamination.
Green tea is made from the leaves of the Camellia sinensis plant. We usually drink tea when we want to slow down and relax, or we want to stay alert and focused. The ingredients in tea, such as caffeine and l-theanine, are widely studied for their benefits on health.
The green tea leaf has been shown to contain a higher concentration of caffeine than black or oolong tea leaves, up to three times more than black tea leaves. This makes green tea a stimulant drink containing approximately half the level of caffeine found in coffee beans (approximately 50 mg per cup vs 100 mg per cup).