The overlooked cooking garnish that’s a secret brain-boosting ingredient
That rosemary sprig on your dinner plate does more than just add flavor to fish or roasted potatoes – it may also give your brain a boost.
A 2024 study in Biomedicine & Pharmacotherapy found that fresh rosemary may help protect brain tissue, sharpen memory, and support the glymphatic system – a waste clearance system in the central nervous system that flushes out metabolic waste from the brain during sleep.
So can rosemary tea or a sprinkle of the fresh herb really help your cognition?
Daily Mail asked nutrition experts. Their answer: possibly – and it comes down to biochemistry.
What’s in Rosemary and Why It May Matter for Your Brain
Rosemary gets much of its potential punch from natural compounds such as 1,8-cineole, rosmarinic acid, and carnosic acid.
Research in Therapeutic Advances in Psychopharmacology found a link between blood levels of 1,8-cineole after taking rosemary extract and cognitive performance.
The study found that in people exposed to rosemary essential oil aroma who had higher levels of 1,8-cineole in their blood had better cognitive performance on several tasks.
Scientists think 1,8-cineole may help support cognition by slowing the breakdown of acetylcholine, a neurotransmitter involved in memory, attention, and executive function.
Rosemary gets much of its potential punch from natural compounds such as 1,8-cineole, rosmarinic acid, and carnosic acid
By allowing acetylcholine to remain active longer, the compound could potentially enhance communication between brain cells, although more research is needed to confirm exactly how it affects cognitive performance in humans.
‘The underlying biochemistry of rosemary is fascinating, but we have to distinguish between preliminary science and real-world results,’ says Anne Till, a registered dietitian with Anne Till Nutrition Group based in North Carolina.
Where Early Promise Meets Real-World Human Evidence
The findings are promising, but experts say lab results shouldn’t be mistaken for proven benefits in everyday diets.
‘While the biological mechanisms are plausible, claims that eating rosemary “actively shields” brain tissue, “clears brain waste overnight,” or prevents dementia overstate the evidence,’ Till told Daily Mail.
Till further notes that most neuroprotective evidence is still preclinical, coming mainly from rodent and cell models rather than rigorous human trials.
Human studies also suggest dose matters.
‘For example, research demonstrates that lower doses of powdered leaf [rosemary] around 750 mg improved alertness and speed of memory, whereas higher doses of 6,000 mg actually impaired performance,’ continues Till.
Other experts agree that more research is needed.
‘Evidence for long-term cognitive benefit, efficacy in dementia, or use in clinical populations is very limited; larger clinical trials are needed,’ adds Julia Zumpano, a dietitian at the Center for Human Nutrition at the Cleveland Clinic.
How Cooking Changes Rosemary’s Helpful Compounds
How you prepare rosemary can affect how many bioactive compounds make it to your plate.
‘Its aroma and some of its benefits are most pronounced when rosemary is freshly chopped or used raw,’ explains Zumpano.
She also notes that high temperatures and extended cooking times lead to significant loss of 1,8-cineole through thermal evaporation.
Preparation also shapes flavor and impact.
‘Finely chopping rosemary releases its aromatic oils and helps distribute or infuse its flavor evenly throughout a marinade or dish, avoiding an overpowering bite,’ says Gabrielle Zalecky, a culinary medicine educator at Cleveland Clinic in Ohio.
‘Shorter cooking times preserve its fresh, bright flavors, which is often why in recipes we add herbs last in the cooking process.’
Carnosic acid is fat-soluble, so gently simmering rosemary in a healthy fat such as extra virgin olive oil helps draw it out. Steeping the leaves in hot water extracts water-soluble rosmarinic acid, experts said.
Preparation of rosemary shapes flavor and impact – high temperatures and extended cooking times lead to significant loss of 1,8-cineole through thermal evaporation
How Much to Use and When to Be Careful
For most people, rosemary is a safe, healthy addition to meals when used in typical culinary amounts.
‘Typical culinary doses are 1 to 2 teaspoons of dried rosemary or about 1 to 2 tablespoons of fresh rosemary chopped per meal,’ said Zumpano.
But cooking with rosemary isn’t the same as using concentrated extracts or essential oils.
One practical caution, says Till: ‘Concentrated rosemary oils contain high levels of camphor and other terpenes that carry neurotoxic potential if ingested; essential oils should never be consumed orally.
‘And anyone taking blood thinners should exercise caution with concentrated supplements due to potential antithrombotic activity.’
If you’re considering a concentrated product, check with your healthcare provider first.
Women who are pregnant may want to avoid high-dose medicinal teas or extracts because of traditional concerns about uterine stimulation, according to the University of Texas at El Paso – ask your clinician for guidance.
Typical culinary doses of rosemary are 1 to 2 teaspoons of the dried herb or about 1 to 2 tablespoons of fresh rosemary chopped per meal
Easy Ways to Use Fresh Rosemary in the Kitchen
Rather than treating rosemary like a miracle cure, the experts suggest enjoying it for what it is: a flavorful, antioxidant-rich addition to whole-food meals.
‘Rosemary is a fantastic, aromatic herb that brings tremendous flavor and antioxidant value to a wide variety of dishes, even if we view it as a culinary joy rather than a “brain cure,”‘ Till told Daily Mail.
The practical approach is simple.
‘Add rosemary as a seasoning in salad dressings, infused oils or butter, and sauces, roasted vegetables, potatoes, winter squash, and summer squash,’ suggests Zumpano.
For an easy dinner, toss root vegetables with extra virgin olive oil, minced garlic, and fresh rosemary, then roast on a sheet pan.
It’s simple, flavorful and nutritious.
‘Rosemary is a dependable, flavorful herb that holds up well in a wide variety of cooking applications.’ adds Zalecky.
The Takeaway
The bottom line: Rosemary contains 1,8-cineole and rosmarinic acid, compounds linked to enzyme inhibition and antioxidant support.
It may complement brain-healthy eating, but it won’t reverse cognitive decline or clear brain waste overnight. The good news, however, is that rosemary will add more flavor and nutritional value to your everyday meals.
