As Naidoo previously told mindbodygreen, guarana has been used for thousands of years by Indigenous communities in the Amazon2 for its naturally stimulating effects.
Traditionally, the powder of guarana seeds, in particular, is consumed in tea or mixed into beverages, Naidoo says, adding, “But in the modern market, it’s largely available in energy [drinks] and soft drinks.
So for this study, researchers wanted to review the existing research on guarana seeds, particularly looking at how consumption of guarana seeds impacted factors like cognition tests, performance time, accuracy, etc.
The team identified eight placebo-controlled studies that met the inclusion criteria, providing data on 328 participants. This review and meta-analysis showed that guarana ingestion resulted in faster performance during a variety of cognitive tasks—without affecting the accuracy—compared to those participants who took a placebo.
“Whether the changes were linked to the caffeine content or other bioavailable substances in guarana is unknown,” the study authors note, adding that additional studies are needed to better understand the relationship between guarana, caffeine, and cognition.