It is typically prepared as a dried whole herb or a dried powdered extract, while teas and liquid extracts are made from fresh or dried leaves.
The herb has been hailed since ancient times for its medicinal properties. Rosemary was traditionally used to help alleviate muscle pain, improve memory, boost the immune and circulatory system, and promote hair growth.
This Medical News Today Knowledge Center feature is part of a collection of articles on the health benefits of popular foods.
Possible health benefits of rosemary
Rosemary has leaves shaped like needles
and pink, white, blue, or purple flowers.
Rosemary is a member of the mint family Lamiaceae, along with many other herbs, such as oregano, thyme, basil, and lavender.
The name rosemary derives from the Latin ros meaning "dew" and marinus meaning "sea" - "sea dew."
Antioxidants and anti-inflammatory compounds
Rosemary is a rich source of antioxidants and anti-inflammatory compounds, which are thought to help boost the immune system and improve blood circulation.
Laboratory studies have shown rosemary to be rich in antioxidants, which play an important role in neutralizing harmful particles called free radicals.
In Europe, rosemary is often used to help treat indigestion. In fact, Germany's Commission E has approved rosemary for the treatment of indigestion. However, it should be noted that there is currently no meaningful scientific evidence to support this claim.
Enhancing memory and concentration
According to research outlined in Therapeutic Advances in Psychopharmacology, the aroma from rosemary can improve a person's concentration, performance, speed, and accuracy and, to a lesser extent, their mood.
Scientists have found that rosemary may also be good for your brain. Rosemary contains an ingredient called carnosic acid, which is able to fight off damage by free radicals in the brain.
Prevent brain aging
Some studies have suggested that rosemary may significantly help prevent brain aging. The therapeutic ability of rosemary for prevention of Alzheimer's shows promise, but more studies are needed.
Another study, published in Bioscience, Biotechnology and Biochemistry, concluded that rosemary may be useful as an anti-inflammatory and anti-tumor agent.
In addition, a report published in the Journal of Food Science revealed that adding rosemary extract to ground beef reduces the formation of cancer-causing agents that can develop during cooking.
Protection against macular degeneration
A study published in the journal Investigative Ophthalmology & Visual Science, led by Dr. Stuart A. Lipton, Ph.D. and colleagues at Sanford-Burnham Medical Research Institute, revealed that a carnosic acid, which is a major component of rosemary, can significantly promote eye health.
This could have clinical applications for diseases affecting the outer retina, such as age-related macular degeneration - the most common eye disease in the United States.
Precautions and side effects
Rosemary is usually safe when taken in low doses. However, extremely large doses can trigger serious side effects, although this is rare.
Side effects include:
- pulmonary edema (fluid in the lungs)
High doses of rosemary may cause miscarriage; therefore it is not advisable for pregnant women to take any supplemental rosemary.
Rosemary can affect the way that some medications work.
Rosemary can affect the activity of some medications, including:
- Anticoagulant drugs - including blood-thinning medications, such as Warfarin, Aspirin, and Clopidogrel.
- ACE inhibitors - which are used for treating high blood pressure. They include lisinopril (Zestril), fosinopril (Monopril), captpril (Capoten), and elaropril (Vasotec).
- Diuretics - such as hydrocholorothiazide and furosemide (Lasix), which increase the passing of urine.
- Lithium - which is used to treat the manic episodes of manic depression. Rosemary can act as a diuretic, and subsequently cause lithium to reach toxic levels in the body.
Have you enjoyed reading about the potential health benefits of rosemary? Take a look at our collection of articles about other foods.
Alternatively, read our article about the top 10 healthy foods for your daily diet.