1. It is high in antioxidant polyphenols
Green tea has more health benefits than black tea, which can be attributed to its lack of processing. Green tea is higher in protective polyphenols. The major polyphenols in green tea are flavonoids, the most active of which are catechins and epigallocatechin gallate (EGCG), which function as powerful antioxidants.
Antioxidants are known to protect the body against disease and are an important part of a healthy diet. Antioxidants can be found in a range of fruits, vegetables and other unprocessed foods. As part of a balanced diet, green tea can be a good source of antioxidants.
2. It may boost brain function
Green tea contains a key active ingredient, caffeine, which is a known mental stimulant. Green tea also includes the amino acid L-theanine, which creates a relaxing effect by increasing the activity of the inhibitory neurotransmitter GABA. It also increases dopamine and the production of alpha waves in the brain which regulate mental alertness.
3. It may boost fat burning
According to some research, green tea can boost metabolic rate and increase fat burning due to its thermogenic properties (which extend beyond the effect of caffeine). However, not all studies have found an increase in metabolism and so the effect may vary with individuals and test conditions.
Other potential health benefits
There are many more health claims surrounding green tea from a reduced risk of cancer to weight loss. The evidence to support these claims is largely inconclusive. Some of the health claims are based on ancient Eastern traditions, where green tea has been used to treat symptoms of disease for years. Because of the proposed benefits, many ‘health’ products now include traces of green tea. However, there is limited evidence to suggest these products are effective. If you are hoping to use green tea for medicinal purposes, make sure to consult your doctor first.
How much caffeine does green tea contain?
Green tea does contain caffeine, although varieties and brands may differ. An equal quantity of green tea contains less caffeine than coffee (one cup of green tea contains approximately 35-80 mg compared to approximately 100-400 mg in the same size cup of coffee), but it can still act as a stimulant. As a result, some people find that drinking green tea increases energy levels, concentration and mood, but this effect may vary between individuals.
If you are sensitive to caffeine, it is advisable to limit the total number of cups of green tea you drink in a day. Too much caffeine can disrupt sleep patterns. If this affects you, try cutting back on caffeinated drinks after lunchtime.
Can green tea affect iron levels?
Like all types of tea, green tea contains tannins. Tannins can interfere with the absorption of iron so try not to drink tea with an iron-rich meal and leave at least one hour before drinking tea after an iron-rich meal.