A Pilot Study of the Acute Ingestion of No. 1 Rosemary Water: Evidence of Cognitive, Physiological and Subjective Effects in Healthy Adults

This study investigated the potential impact of the acute ingestion of No. 1
Rosemary water—a commercially available carbonated water containing an
extract of Rosemary (Rosmarinus officinalis ). Twenty healthy adults were
randomly allocated to consume either 330 ml of No. 1 Rosemary water or
plain carbonated water. They then completed a series of subjective measures
and cognitive tasks including a fifteen-minute session on a stress inducing
multi-tasking framework, followed by a second completion of the subjective
measures. Heart rate and blood pressure were monitored throughout the procedure.
Given the pilot nature of the study, analysis of the data eschewed significance
testing for the calculation of Cohen’s d measure of effect sizes. These
revealed a number of small enhancement effects on cognition, consistent with
those found previously for the inhalation of the aroma of Rosemary essential
oil, and oral administration of dried herb. Of particular interest here are the
reduced subjective evaluations of stress, and the blunted physiological reactivity
noted for heart rate and blood pressure, which represent novel findings in
this area. Taken together the data suggest further investigation of this product
is warranted with regard to its potential beneficial properties.