This Common Herb May Help To Fight Alzheimer's, Anxiety And Poor Sleep

Though not all of our brain health risk is in our control, some promising studies have found links between our diet and both future and current brain well-being.

Alzheimer’s Society UK recommends a diet rich in whole grains, fruit, veg and fish as they advise a “lifelong approach to good health is the best way to lower your risk of dementia.”

Some researchers suggest, meanwhile, that there is “a bi-directional relationship between the microbiome and anxiety,” while diets lower in fibre and higher in sugar have been associated with poorer, less satisfying sleep.

Rosemary, which has been linked to improved blood flow to the brain, may be beneficial for all three.

A compound in rosemary has been linked to better dementia outcomes in mice

A paper published in the journal Antioxidants found an association between a derivative of carnosic acid, present in herbs like rosemary, and the removal of proteins linked to Alzheimer’s in mice. 

Carnosic acid has been linked to “neuroprotective” (brain-boosting and healing) properties in previous studies, and it’s also known for its anti-inflammatory and antioxidant effects.

But in its pure form, carnosic acid is unstable and hard to keep and dose out in predictable, unoxygenated concentrations.

So, the scientists behind this research created a synthetic version of the acid called diAcCA. This is much more stable, the scientists say. 

When scientists tested diAcCA on mice with amyloid plaques linked to Alzheimer’s, the harmful proteins were reduced with no observed negative side effects.

The study’s lead author said: “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.” 

What other benefits might rosemary have?

A 2024 double-blind, randomised trial found that “rosemary as a traditional herb could be used to boost prospective and retrospective memory, reduce anxiety and depression, and improve sleep quality” among participants, who were all university students. 

A 2020 study found that Japanese men with mood disturbances saw improved mood and better sleep after four weeks of rosemary extract.

Additionally, the consumption of rosemary tea has been linked to fewer depression and anxiety biomarkers among healthy volunteers.

And a 2021 paper linked lavender and rosemary aromatherapy to better cognitive function, lower anxiety, and improved sleep among elderly people with diabetes. 

Further research is needed to work out exactly what kind and dose of rosemary is needed to achieve every potential benefit, but in the meantime, the surprisingly iron, calcium, and vitamin B6-rich herb seems very likely to improve your mood, sleep, and stress levels.