Investigation of rosemary herbal extracts (Rosmarinus officinalis) and their potential effects on immunity

The discovery of new curative drugs and the consumption of natural dietary ingredients with the ability to exhibit immunomodulatory activity is urgently needed to decrease the risk of chronic diseases among the population. Rosmarinus officinalis (Lamiaceae) is an aromatic plant that has been traditionally and medicinally used as a carminative, antispasmodic, painkiller, circulatory tonic, to stimulate hair growth and to improve memory dysfunction. This study aimed to assess the potential effects of rosemary solvent extracts on human immune function. Science Direct, Web of Science, Wiley, Elsevier, PubMed, Scopus, and the Google scholar search engines were used to retrieve relevant information included combinations of "rosemary" or "R. officinalis" with "immune function," "immunity," "immune system," "anti-inflammatory," "inflammation," or "health benefit." A number of studies have been found a stimulatory effect of rosemary and its active compounds on the immune system in vitro and animal study, but there is a lack of evidence in humans for supporting this. The results demonstrated the potential of rosemary and its main active components as dietary ingredients with immunomodulatory functionality. Human studies should be performed and a double-blind randomized controlled trial would be ideal.