If you have a stomachache, a cup of warm tea without sugar may reduce the pain..

May be it is because of the amino acid L-theanine (found most readily in green, black, oolong and pekoe teas) may help the body's immune system response when fighting infection, by boosting the disease-fighting capacity of gamma delta T-cells. which play a central role in cell-mediated immunity.

Stress can also be the cause of stomacache , and L-theanine can increase alpha wave production in the brain, which is associated with a state of "alert relaxation".
Black Tea can help to lower stress-hormone level ( it can help to drop the cortisol ; hormone produced by the adrenal cortex that is involved in the response to stress.

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