Carnosic acid is a phenolic diterpene found primarily in rosemary (Rosmarinus officinalis) and sage (Salvia officinalis). Its use to support memory and brain function is grounded in emerging scientific research, primarily from preclinical studies. Laboratory and animal studies have shown that carnosic acid exhibits neuroprotective properties, largely attributed to its antioxidant and anti-inflammatory effects. For example, carnosic acid has been observed to activate the Nrf2 pathway, which plays a crucial role in cellular defense against oxidative stress, a factor implicated in neurodegenerative diseases such as Alzheimer’s disease.

Some animal studies suggest carnosic acid may help protect neurons from amyloid-beta toxicity and improve cognitive performance in models of Alzheimer’s disease. It may also inhibit acetylcholinesterase, an enzyme that breaks down acetylcholine, thereby supporting cholinergic function important for memory. However, while these results are promising, human clinical trials directly assessing carnosic acid supplementation for cognitive function or memory are lacking as of 2024. Most evidence comes from in vitro or animal models, and thus cannot be directly extrapolated to humans.

In summary, the use of carnosic acid for memory and brain function is supported by some scientific evidence, but this evidence is preliminary and mainly preclinical. More robust human studies are needed to confirm its efficacy and safety for this purpose.