Rosemary is gaining new attention not only for its fragrant leaves but also for its effects on memory, anxiety, and cognitive health.
According to a Knowridge report published June 8, 2025, this aromatic herb may even help protect the brain from Alzheimer’s disease.
Used for centuries, rosemary (Rosmarinus officinalis) was believed to sharpen memory and boost concentration in ancient Greece and Rome. Today, science supports those early beliefs. One study found that participants exposed to rosemary’s scent performed better on memory tests than those in a scent-free environment.
How Rosemary May Support Brain Health
The herb affects the brain through several pathways. It improves blood flow to the brain, which can enhance mental clarity. Rosemary’s aroma also appears to lower anxiety levels and aid sleep quality—two factors that contribute to better memory retention.
Compounds in rosemary, including 1,8-cineole, play a role in protecting neurotransmitters. This particular compound slows the breakdown of acetylcholine, a chemical vital for learning and memory. Preserving acetylcholine levels may be especially helpful as the brain ages.
Additionally, rosemary is high in antioxidants that shield brain cells from oxidative stress, a major contributor to cognitive decline.
Promising Alzheimer’s Research
One of rosemary’s key antioxidants is carnosic acid. In 2025, researchers developed a new version called diAcCA, designed to remain inactive until it reaches inflamed brain regions. This targeted approach may reduce side effects.
In pre-clinical mouse studies, diAcCA improved memory, increased synapses—the connections between brain cells—and reduced toxic Alzheimer’s-related proteins such as amyloid-beta and tau. No toxicity has been reported so far.
“What’s especially exciting is that diAcCA only activates in inflamed brain regions, which could minimise side effects,” researchers noted.
Beyond Alzheimer’s, diAcCA may have potential in treating other inflammatory conditions like Parkinson’s disease, cardiovascular disease, and type 2 diabetes.
More Benefits Beyond the Brain
Rosemary’s advantages aren’t limited to cognitive function. Traditionally used for digestion and inflammation, rosemary also contains compounds like rosmarinic acid and ursolic acid, both known for their anti-inflammatory properties.
There’s emerging evidence that rosemary may soothe skin conditions like acne and eczema. Carnosic acid also helps protect skin from UV damage, offering possible anti-ageing effects.
Its oil has antimicrobial effects and may be used in preserving food or preventing microbial growth in pharmaceutical settings.
Safety and Use
When used in food, tea, or aromatherapy, rosemary is generally considered safe. However, concentrated extracts may lead to side effects, especially at high doses. These can include nausea or, in rare cases, seizures—particularly in people with epilepsy.
There’s also concern that high doses could trigger uterine contractions, so pregnant individuals should consult a doctor before using rosemary in supplement form. Since rosemary can interact with medications like blood thinners, medical advice is recommended for those considering high intake.
Article updated 3 weeks ago. Content is written and modified by multiple authors.
