For more details on this topic, see deuterium. A deuterium atom contains one proton, one neutron, and one electron. 2H (atomic mass 2.013553212724(78) u), the other stable hydrogen isotope, is known as deuterium and contains one proton and one neutron in its nucleus.
The caffeine in green tea, especially when taken in large amounts, can worsen diarrhea. Irritable bowel syndrome (IBS) : Green tea contains caffeine. The caffeine in green tea, especially when taken in large amounts, can worsen diarrhea and might worsen symptoms of IBS.
Allergy Symptoms. How you feel after you drink a cup of tea may vary. Common allergic reactions not only include hives and itchy skin but also eye irritation and tearing, runny nose, sneezing, difficulty breathing, upset stomach, diarrhea, tingling in the mouth, swelling of the throat or asthma.