Abstract The incidence of cognitive disorders is rising and medications to address cognitive impairments are limited. Phytochemical compounds have had some success in improving cognitive outcomes in preclinical studies. However, the evidence surrounding the implementation of these compounds routinely in (1) improving cognition in healthy individuals or (2) as prophylaxis and treatment against the cognitive sequelae of neurological insult, has not been collated. To address this, the evidence base surrounding the impact of phytochemical agents on cognitive function in healthy individuals were reviewed. Web of Science, PubMed, PsycNET, and AYUSH Research Portal were systematically searched for double-blind and single-blind randomized controlled trials assessing the efficacy of Curcuma longa, Bacopa monnieri, Ocimum tenuiflorum, Camellia sinensis, Centella asiatica, Ganoderma lingzhi, and Rosmarinus officinalis, on cognitive function. Seven studies met inclusion. These examined the impact of either B. monnieri, O. tenuiflorum or C. sinensis. No benefit of B. monnieri or C. sinensis processing speed, attention, working memory, language, psychomotor function or overall cognitive performance. O. tenuiflorum improved reaction times on an executive function task. Further, more methodologically robust trials are recommended of longer duration to investigate the efficacy of phytochemical supplementation for cognition.
Marsh et al. (Thu,) studied this question.