Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Very effective!!

I rarely write reviews but i have to admit, these vitamins really do work...I am deployed and therefore was always in a stressful mood, once my friend suggested me to take a dose of them, i actually felt the stress fly away and became much more relaxed in every aspect....I took them since that time and still feel the effects, i did a huge amount of research to find any side effects but it seems that it is safer than anything else so i will continue therefore!!!!