Effects of the consumption of guarana on human health: A narrative review

Abstract

Guarana (Paullinia cupana) is a plant from the Amazon region with cultural importance. Despite its early ancestral use by indigenous tribes, the first reports regarding the benefits of guarana consumption for human health were published in the 19th century. Since then, the use of guarana seed in powder and extract forms has been studied for its diverse effects on human health, such as stimulating, anti-inflammatory, antioxidant, anticancer, hypocholesterolemic, and antiobesity effects. These effects are attributed to the high content of bioactive compounds found in guarana seeds, especially methylxanthines and flavonoids. In fact, the Brazilian Food Supplement Law has officially acknowledged guarana as a source of bioactive compounds. The number and diversity of studies focused on guarana and human health are increasing; thus, organizing and describing the available evidence on guarana and its applications is necessary to provide a framework for future studies. In this narrative review, we have organized the available information regarding guarana and its potential effects on human health. Guarana produces unique fruits with great potential for human health applications. However, the available evidence lacks human studies and mechanistic investigations. Future studies should be designed considering its applicability to human health, including intake levels and toxicity studies.

Revisiting the Oxidation of Flavonoids: Loss, Conservation or Enhancement of Their Antioxidant Properties

“…Comparatively, lesser but still substantial evidence also exists for the ability of these compounds to exert some antioxidant actions in vivo. In fact, a number of studies in humans and animals have revealed that the increase in several markers of biological oxidation induced by ROS, such as F2-isoprostanes, hydroperoxyoctadecadienoic acids, 8-hydroxy-2′-deoxyguanosin, oxidized low density lipoprotein, nitrotyrosine and other nitrosylated or carbonylated amino acids and proteins, can be effectively prevented or ameliorated by the ingestion of certain flavonoid-rich plant foods or the administration of either flavonoid-rich extracts or pure flavonoids, as reviewed by several authors [ 46 , 47 , 48 , 49 ]. The broad recognition of the latter effects of flavonoids is likely to account for the so generalized and long perception that “flavonoids act primarily as antioxidant molecules”.…”

The potential of functionalized dressing releasing flavonoids facilitates scar-free healing

“…When compared to controls, patients with pulmonary tuberculosis who received a combination of catechins and antituberculosis showed a significant increase in blood levels of reduced glutathione, an antioxidant effect that plays an important role in the human oxidative stress mechanisms ( 68 ). In addition, the levels of ROS metabolites such as F2-isoprostaglandins are considerably reduced when flavonoids are consumed over time ( 69 , 70 ).…”

Dinâmica de metabólitos e produção de frutos durante a safra de guaraná

“…Hodiernamente pesquisadores confirmaram os benefícios associados ao consumo das sementes de guaraná vão além das propriedades estimulantes ocasionadas pelos altos teores de cafeína (Schimpl, Silva, Gonçalves, & Mazzafera, 2013).pois essas sementes também possuem polifenóis com diversos benefícios na suplementação humana. Altos teores de metilxantinas e flavonóides presentes nessa espécie são biodisponíveis e contribuem para reduzir o estresse oxidativo de indivíduos por ação antioxidante com efeitos estimulantes, anti-inflamatórios, anticancerígenos, hipocolesterolêmicos e antiobesidade (Torres et al, 2022).…”