So of course when I saw it in Brazil, I was rather excited. Let's be honest, I had no idea what was actually in these guarana drinks but eventually I started drinking them daily and my mom also ordered them regularly. We sampled the Guarana Antarctica and the Kuat Guarana sodas (as a side note -- AmBev produces Guarana Antarctica (the most popular brand in Brazil, which amongst other things, hosts the Guarana Antaractica Street Festival and paired up with Brazilian designer Osklen in 2005) and Coca Cola sells Kuat Guarana).
Out of curiosity this morning, I googled Guarana to find the Guarana Antarctica website. For some reason, I knew it sounded familiar (even before drinking it in DC), but wasn't sure why. And then I realized why... a friend had mentioned it to me months ago (perhaps a year or more now) as an alternative to caffeine. Guarana contains a high level of guaranine, a substance with similar characteristics as caffeine. In fact, my brief googling has revealed to me that Guarana Antarctica has a caffeine content equivalent to most energy drinks and the berry has two to three times the caffeine of a coffee bean! Looking back, I don't recall feeling the effects of the caffeine (but maybe is more of an indication that caffeine is affecting me less and less... oops). Aside from the energizing qualities of guarana, some believe that guarana has medicinal effects.
Whatever the effects of guarana, I enjoyed it. Although I probably won't seek it out, if I find it on a local menu, I'm almost certain to try it again.