I think that theanine, especially considering its expensive price, should only be taken when under some sort of abnormally high stress as assistance, rather than on a regular basis. Otherwise, simple and cheap sucrose is a much better option to reduce and reverse the stress reaction. Tastes better too! But I will buy some Theanine and post my results. What is the best source, do you guys think?A low dosage of theanine completely reversed these changes, while having virtually no effect on the healthy control group.