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.
Caffeine in green tea can stimulate the body. Some medications used for depression can also stimulate the body. Taking green tea that contains caffeine along with some medications for depression might cause serious side effects including fast heartbeat, high blood pressure, nervousness, and others. Some of these medications used for depression include phenelzine (Nardil), tranylcypromine (Parnate), and others.