A research study has identified a common ingredient that can be added to your diet to help improve memory and combat Alzheimer’s disease, the leading cause of dementia.

Published in the peer-reviewed, open-access Antioxidants journal, the paper cites a compound found in the aromatic herb, which is readily available in most kitchens, that boosted the memory of mice and showed other signs of counteracting cognitive decline.

Rosemary has long been linked to better memory, with references from ancient Greece and Rome that students would consume the shrub to improve concentration.

William Shakespeare even gave a nod to its brain-fuelling abilities in Hamlet, with Ophelia stating, “There’s rosemary, that’s for remembrance; pray you, love, remember.”

In the study, scientists from San Diego’s Scripps Research Institute synthesised a stable form of the compound diAcCA, found in rosemary. which is converted to carnosic acid in the gut before entering the bloodstream.

When used to treat mouse models of Alzheimer’s disease, diAcCA led to improved memory and synaptic density, the number of connections between neurons within a specific area of brain tissue.

The latter sign fights cognitive loss, as Alzheimer’s is closely associated with a decline in neuronal synapses, meaning offsetting this could slow the disease.

“By combating inflammation and oxidative stress with this diAcCA compound, we actually increased the number of synapses in the brain,” explained senior author, Stuart Lipton, MD, PhD.

“We also took down other misfolded or aggregated proteins such as phosphorylated-tau and amyloid-β, which are thought to trigger Alzheimer’s disease and serve as biomarkers of the disease process.”

Sample tissue used in the tests showed diAcCA also reduced brain inflammation, with the drug being activated by the same inflammation it then combats, meaning it is only active in damaged brain tissue.

Dr Lipton continued: “We did multiple different tests of memory, and they were all improved with the drug. And it didn’t just slow down the decline; it improved virtually back to normal.”

Rosemary has previously been found to stimulate blood circulation, including to the brain, which in turn delivers more oxygen and nutrients and is why it has been associated with upping concentration levels.

It contains other compounds, such as 1,8-cineole, “which helps prevent the breakdown of acetylcholine, a brain chemical essential for learning and memory,” Dipa Kamdar, a Senior Lecturer in Pharmacy Practice at Kingston University, contends.

This may also support cognitive performance through our later years.

Dr Lipton’s study adds that no signs of toxicity have been found in the mice used for testing, raising potential hopes for a human trial to be on the horizon.

The professor also believes diAcCA could work alongside currently available Alzheimer’s treatments by “limiting their side effects” such as brain swelling or bleeding.

If successful, rosemary could also be used as a treatment for other inflammatory conditions, such as type 2 diabetes, heart disease, Parkinson’s disease and others.