Green tea is known for its potential health benefits and may lower the risk of several chronic health conditions. Drinking green tea in very large amounts may raise the risk of gastrointestinal ...

Drinking green tea with L-theanine can cause calm alertness because the caffeine in the tea wakes you up, while L-theanine promotes relaxation.

Medically reviewed by Aviv Joshua, MS, RDN Key Takeaways Black tea has more caffeine than green tea.Green tea and black tea ...

Green tea's impact shifts with the time of day, offering morning alertness and metabolic support, while evening consumption can be calming but risks sleep disruption. Circadian rhythms and caffeine ...