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Green tea
緑茶 / 綠茶
A listing is not a recommendation.
Origin: China and Japan · Tradition: East Asian tea culture · Food & herbs
What it is
An infusion of tea leaves that have been steamed or pan-fired. As an everyday drink it is widely studied around the world. It contains caffeine.
A short introduction (not a treatment instruction)
- Drink a moderate amount as tea, with meals or in the afternoon.
- Strong tea just before bed can contribute to sleeplessness.
- Treat concentrated extracts aimed at a health outcome as distinct from a drink, and consult a physician.
Symptoms or aims often mentioned with this practice
- Focus and thinking
- Tiredness
- Constipation or digestion
Research notes (this is not a promise of effect)
C: Preliminary, small, or lower-quality studies, or mixed results. These notes should not be over-read
There are many observational studies of habitual green-tea drinking and lifestyle-related disease. Liver injury has been reported with extracts. It is not a medicine for a specific symptom. NCCIH summarises safety and the state of the research.
Sources
Safety notes
Caffeine sensitivity, sleeplessness, and stomach unease. Liver injury has been reported with green-tea extracts (supplements).
If you are unsure, or if you have a health condition, are pregnant, or take medicine, consult a qualified professional.
Situations in which this is better avoided
- People who should avoid caffeine
- Concentrated extracts in people with liver disease
- Interactions with some medicines (consult a professional)