A high daily intake of fruits and vegetables is an important strategy to promote health. The mechanism explaining the health benefits of plant food materials is attributed, at least in part, to their high content of bioactive phenolics. Guarana (Paullinia cupana) is a typical product from Amazon biota and, mainly as a source of caffeine; its seeds are commonly used as stimulants. However, guarana seeds are also rich in catechin, epicatechin, procyanidin B1, and procyanidin B2. Guarana exhibits potential health benefits in cognitive function and prevention of cardiovascular disease. Furthermore, it is a promising source of antihyperglycemic and antibacterial compounds for prevention and/or management of type 2 diabetes and oral diseases. However, to confirm these benefits in humans, clinical trials are needed to provide evidence to support these anecdotal observations.