Herb Garden

Cognitive Function and Memory Enhancement
Rosemary has a long traditional history as a "brain tonic," and modern clinical trials support its efficacy in enhancing cognitive performance. The primary mechanism of action appears to be the inhibition of acetylcholinesterase (AChE) by compounds such as 1,8-cineole and rosmarinic acid, which prevents the breakdown of the neurotransmitter acetylcholine, essential for memory and focus. [1,2] Clinical studies on healthy adults have shown that exposure to rosemary aroma or ingestion of extracts significantly improves performance in speed of memory and overall alertness (secondary memory factors). [3,4] In a study regarding academic performance, pupils exposed to rosemary aroma demonstrated significantly higher overall test scores compared to controls. [5] Furthermore, low-dose ingestion of dried rosemary powder was found to improve memory speed in elderly subjects, suggesting a restorative capability for age-related cognitive decline. [6]

Neuroprotection and Mood Modulation
Beyond immediate focus, rosemary offers neuroprotective properties vital for long-term brain health. The diterpenes carnosic acid and carnosol exhibit potent antioxidant activity, protecting neurons from oxidative stress and excitotoxicity, effectively scavenging free radicals in the brain. [7,8] These compounds also display anti-inflammatory effects within the central nervous system, which is crucial for maintaining cognitive stamina during periods of high mental workload. [9] additionally, studies indicate that rosemary administration can reduce anxiety and improve mood scores, likely through the modulation of dopaminergic pathways, creating a calmer state conducive to concentration. [3,10]

Toxicity
Classed as Generally Recognized As Safe (GRAS) for food use. Toxicity studies indicate a high safety margin; in animal models, extracts showed low acute toxicity with an LD50 >2000 mg/kg. [11,12] No genotoxicity or mutagenicity was observed in standard assays. [11] However, extremely high doses (far exceeding therapeutic or culinary use) of essential oil components specifically may have convulsant properties due to camphor content, though this is not typically observed in standard whole-herb or water-soluble extract preparations. [13]