Why is black tea so soothing?

Black tea is soothing due to a unique combination of L-theanine, an amino acid that promotes relaxation, and a slow-release form of caffeine that provides calm focus rather than jitters. It lowers the stress hormone cortisol, while the ritual of drinking it provides psychological comfort, offering a "relaxed alertness". 
Key Reasons for Black Tea’s Soothing Effects:
    L-Theanine & Relaxation: Black tea contains L-theanine, which reduces anxiety and promotes relaxation by boosting alpha brain waves.
    Calm Energy (Not Jitters): Unlike coffee, the caffeine in black tea is released gradually over several hours, offering sustained focus without a crash.
    Reduced Stress Hormones: Studies found that regular tea drinkers have lower levels of cortisol (the stress hormone) after stressful events, indicating it helps people recover from stress faster.
    Psychological Ritual: The ritual of preparing a hot cup of tea provides a mental break and comfort.
    Antioxidants: Rich in polyphenols and catechins, it helps combat oxidative stress.
    Mood Improvement: It increases feel-good hormones like serotonin. 
For the best calming effect, black tea should be brewed for 3-5 minutes.