The benefits of rosemary oil and how to use it

The benefits of rosemary oil and how to use it

Rosemary is not just any ordinary herb that you sprinkle on top of your favorite dish. It's much more than that. In fact, rosemary essential oil is one of the most potent oils out there.

Rosemary comes with a lengthy history of use in various cultures around the world, including ancient Greece, ancient Rome and medieval Europe, who used it for culinary and medicinal purposes. It was also traditionally used for religious ceremonies, being worn by brides as a symbol of loyalty and devotion to their spouses, and was believed to be able to ward off evil spirits and to prevent the onset of the bubonic plague. In traditional Chinese medicine, it is used to improve digestion, whereas the Native Americans used it to treat headaches and respiratory problems.

What is rosemary oil? 

Rosemary essential oil comes from the Rosmarinus Officinalis plant, an evergreen shrub which belongs to the Mint family. While sometimes called a "rosemary tree," it does not grow into a full-sized tree. Instead, it typically grows up to four to six feet tall and has a woody stem with many branches covered in needle-like leaves. In Spanish-speaking countries, it is known as "romero."


This plant is native to the Mediterranean and received its name from the Latin words “ros” (dew) and “marinus” (sea), meaning “dew of the Sea,” though it is also grown in many other parts of the world today, some of the largest producers being in Spain, France, Morocco, Tunisia and the United States.

Rosemary’s fragrant oil, characterized by an invigorating, evergreen, citrus-like, herbaceous scent, is extracted through a distillation process from the leaves and stems of the plant. Rosemary essential oil of higher-ranking quality is solely obtained from the flowering tops of the plant. The leaves of the aromatic Rosemary bush have a high oil concentration and the plant is part of an aromatic family of herbs, which also includes lavender, basil, peppermint and oregano. 

The majority of the positive health benefits of rosemary are believed to come from its primary chemical components—carnosol, carnosic acid, ursolic acid, rosmarinic acid and caffeic acid. These compounds are known for their potent antioxidant activity, which (like clove oil) help to combat free radicals and oxidative stress in the body. By reducing oxidative damage and inflammation, rosemary may offer a variety of health benefits. From improving memory and soothing digestive problems to boosting the immune system and relieving aches and pains, rosemary is a truly remarkable oil. 

We will discuss four of its remarkable benefits here and explain how we use rosemary essential oil in non-toxic insect control.

Rosemary improves memory and concentration


Rosemary is believed to improve memory and concentration by increasing blood flow to the brain and stimulating the central nervous system. Two of its compounds (carnosic acid and rosmarinic acid) have been shown to have neuroprotective effects and may help to prevent the breakdown of neurotransmitters in the brain. 

The Greeks, a clever lot, were known for their innovative methods of improving memory. During ancient Greek times, students would wear rosemary wreaths during exams to aid in their performance and memory retention. And it seems they may have been onto something. A recent study published in the International Journal of Neuroscience evaluated the cognitive performance of 144 participants using rosemary oil for aromatherapy. The study found that “rosemary produced a significant enhancement of performance for overall quality of memory.” Another study, published in Psychogeriatrics, tested the effects of rosemary oil aromatherapy on 28 elderly dementia and Alzheimer's patients, and found that “All patients showed significant improvement in personal orientation related to cognitive function.” 

How to Use: Before a big test in school (for teens and adult students), use this essential oil by making an inhaler with equal part rosemary (rosemary 1,8-cineole is recommended) and lemon. Sniff the inhaler frequently while studying; then just before the test, sniff again several times. A simpler suggestion is to inhale over the bottle of oil. You may also place three to four drops in a diffuser with purified, distilled or filtered water, (depending on the diffuser’s instruction manual).  

Note: An inhaler for essential oils is not the same as a diffuser. A diffuser is a device that disperses essential oils into the air, allowing them to be inhaled and absorbed through the lungs and skin. An inhaler, on the other hand, is a small, portable device that contains a wick or cotton ball soaked in essential oils, which is then placed inside a tube or container that can be held up to the nose and inhaled directly. The purpose of an inhaler is to provide a convenient and discreet way to use essential oils for their therapeutic benefits on-the-go.

Rosemary aids with digestive health

Did you know that rosemary can work wonders for your digestive health? That's right. Rosemary contains compounds that can help ease digestive issues such as bloating, constipation, gas, indigestion and stomach cramps. These compounds have anti-inflammatory properties and can help soothe the digestive system. Additionally, rosemary has been shown to increase the production of bile, which helps to break down and digest fats, and, in doing so, plays a crucial role in digestion. It also stimulates appetite. 

How to use: Add some rosemary to your meals or brew it as a hot tea to help improve your digestive health. To treat stomach ailments, combine one teaspoon of a carrier oil such as coconut or almond oil with five drops of rosemary oil and gently massage the mixture in a clockwise fashion over your abdomen. Trust me, your gut will thank you. 

Rosemary promotes hair retention and stimulates growth


If you spend any amount of time in the essential oil world, you’ll know that rosemary is one of the best essential oils for hair. While there are other essential oils that can address issues like dandruff or lack of shine, rosemary is at the top of the list for its hair growth benefits. It is known for its tonic properties that stimulate hair follicles, which not only promotes hair growth but also strengthens hair strands. It also has the ability to slow down the graying of hair and prevent hair loss. Additionally, the oil can provide moisture to the scalp, thereby alleviating dandruff and other dry scalp conditions.

In fact, two studies, published by the National Library of Medicine and Europe PMC tote rosemary as a “a safe and effective treatment for alopecia areata” (or male pattern balding) and write that those receiving a topical rosemary treatment “experienced a significant increase in hair count.” However, it is important to note that visible improvement may take up to six months of consistent use. 

How to use: I recommend using no more than 1% dilution for regular daily use, as this will help prevent your shampoo from breaking down. (This is approximately five drops of essential oil for one ounce, or two tablespoons, of shampoo.) You can also combine rosemary with other hair and scalp-loving essential oils like cedarwood and lavender to promote healthy hair. Try diluting rosemary in a carrier oil like argan and massaging onto the scalp, at least 10 minutes before shampooing your hair. You can also make a DIY hair rinse by steeping fresh rosemary sprigs in hot water and allowing the mixture to cool before using it as a final rinse after shampooing.

Rosemary can help reduce inflammation throughout the body

Rosemary’s anti-inflammatory properties are beneficial because inflammation is a natural response of the body's immune system to infection, injury or stress. However, chronic inflammation can contribute to the development of many chronic diseases, including heart disease, cancer and arthritis. The anti-inflammatory properties of rosemary can help reduce inflammation throughout the body, including in the skin, gut and joints. This can help alleviate symptoms of conditions like arthritis, eczema and other inflammatory skin disorders. 


Additionally, reducing inflammation can improve overall health and reduce the risk of chronic disease. In fact, a study published by Nutrients states “Rosemary extract and its polyphenols CA and RA have recently been explored and found to exert potent anticancer effects.”

How to use: To use rosemary for skin, you can create a homemade rosemary-infused oil by steeping fresh rosemary sprigs in a carrier oil like olive oil or almond oil. Once the oil is infused with the rosemary, it can be applied directly to the skin. Rosemary essential oil can also be added to carrier oil or lotion and applied topically to the skin.

How does Dr. Killigan’s use rosemary oil? 

For quite some time, I have recognized rosemary oil as a safe alternative to chemical insecticides. Not only is it not harmful to the environment, but it is also non-toxic and biodegradable. As you may be aware, I keep as far away from the toxic game as possible. Not only can insects become resistant to pesticides, but they can also be quite harmful for you, your family, your furry ones and the environment. When there are simpler, safe and healthier options available, why would anyone choose otherwise?

Rosemary oil has both insecticidal and repellent properties, toted for its effectiveness in naturally repelling pests and killing those pests that come into contact with it. This remarkable oil contains several compounds—camphor, cineol and borneol—which have insecticidal properties.

  • Camphor interferes with the nervous system of insects, causing paralysis and death. 
  • Cineol, also known as eucalyptol, acts as a respiratory and nervous system disruptor in insects.
  • Borneol disrupts the pheromone communication system of insects, making it difficult for them to find mates or communicate with each other. 

    Together, these compounds create a physical barrier around the insect, blocking air from its spiracles and preventing breathing, which ultimately causes death on contact—through suffocation. Additionally, this oil has a strong repellent properties for insects. As a result, any insect not sprayed directly will quickly leave the treatment area.

    To give you a few concrete examples of its potency, a study published by the National Library of Medicine found that rosemary essential oil “caused complete mortality of spider mites at concentrations that are not phytotoxic to the host plant,” whereas a study by Cornell University wrote that “rosemary oil had the longest repellent effect on the mosquito Aedes aegypti” (yellow fever mosquito). Furthermore, Research Gate writes that “rosemary essential oil has remarkable insecticidal properties,” causing 100% mortality of adult rice weevils. It’s clear to see that rosemary is a phenomenal oil to use in establishing a pest-free home.

    We are using this remarkable oil in Dust to Dust, a safe, toxin-free, people-friendly and pet-friendly solution against both winged and crawling insects.

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