Rosemary Essential Oil Uses and Benefits
It may stimulate hair growth, reduce pain, and support brain function
Medically reviewed by Arno Kroner, DAOM
Rosemary essential oil is a powerful essential oil. It can be used topically (when diluted) or inhaled as aromatherapy. This essential oil is extracted from rosemary leaves and the flowery tops of the plant.
The scientific name for rosemary is Rosmarinus officinalis. It is a small evergreen plant that is part of the mint family, which includes other herbs, such as basil and sage. Rosemary is commonly found as fresh or dried leaves and is used in various recipes.
Rosemary's benefits have been touted for centuries. There has been an interest in using rosemary essential oil to develop new medicines for treating various conditions.
The benefits of rosemary essential oil are often attributed to the plant's high antioxidant, anti-inflammatory, and neurological properties. Purported benefits include supporting brain health, stimulating hair growth, pain relief, and more.
This article covers the applications of rosemary essential oil, possible health benefits, side effects, and more.
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Applications of Rosemary Oil
According to the U.S. Department of Agriculture (USDA), fresh rosemary is high in vitamins and minerals. It contains vitamins A, C, pyridoxine (B6), folate (B9), and thiamine (B1), and minerals including calcium, magnesium, and iron.
Rosemary is abundant in antioxidants, including carnosic acid, carnosol, and rosmarinic acid. These substances offer various anti-inflammatory, antioxidant, and antimicrobial effects.
Rosemary essential oil can be applied topically or inhaled. The oil is concentrated, so you will need only a few drops at a time. The oil is often sold in small bottles with droppers, making dispensing easier.
Rosemary Formulations
Rosemary is an aromatic herb that can flavor a variety of dishes. When preparing these dishes, you can use fresh or dried rosemary to get this plant's benefits. Fresh and dried leaves can also make rosemary tea and other beverages.
Rosemary extract concentrates the herb's vital compounds into a carrier oil, such as olive oil or alcohol in fragrances. The extract comes in powder or liquid forms or as a supplement. Rosemary liquid extract can be consumed out of the bottle orally or added to a recipe.
Rosemary essential oil is made with rosemary leaves and the flowering part of the plant. It can be used as an aromatherapy or topical skin or hair treatment.
Possible Health Benefits of Rosemary Essential Oil
Research shows many possible benefits of rosemary essential oil for managing common health issues. Here are some ways in which rosemary oil might be helpful.
Hair Growth
One of the most common uses of rosemary essential oil is for stimulating hair growth in people with androgenetic alopecia—a common form of hair loss that mainly affects people assigned male at birth. Rarely, it also impacts people assigned female at birth. This hair loss condition is suspected to be caused by the sex hormone testosterone attacking hair follicles.
Research on rosemary oil used to treat androgenetic alopecia shows it can be as effective as Rogaine (minoxidil), a popular over-the-counter (OTC) hair-regrowth product.
One study reported in 2015 aimed to investigate the clinical efficacy of rosemary oil compared to minoxidil 2% in treating androgenetic alopecia.
The study found applying rosemary oil to the scalp twice daily for six months was just as effective as using minoxidil for the same period. The study also found less itching associated with rosemary oil, suggesting that rosemary may be more tolerable than minoxidil.
Newer research has looked at the possibility of using a hair lotion that includes the extract of the rosemary plant. A 2023 study on mice models focused on the formulation and evaluation of a 1% hair lotion containing the rosemary plant's methanolic extract. Water was used as a control, and 2% minoxidil hair lotion was used as a standard treatment.
Results showed that the 1% rosemary lotion formulation passed all evaluation parameters and showed significant hair growth over the standard treatment. Researchers suggest that lotion may be an alternative to commercially available hair growth products.
Stress Relief and Mood
When inhaled, rosemary oil may offer antistress, antianxiety, mood, and cognitive-enhancing effects. These benefits result from the oil's effects on certain stress hormones like cortisol and feel-good brain neurotransmitters (chemical messengers between nerve cells) like dopamine.
Additional studies have shown that inhaling rosemary oil might help ease depressive and anxious symptoms for some people. Evidence shows when inhaled, aromatic plant oils like rosemary can bypass the blood-brain barrier and target brain tissue through the nasal-brain pathway. They then act on the brain to improve anxiety, depression, and even sleep quality.
Alertness
Some evidence suggests aromatherapy in rosemary oil may help increase alertness. This is because it can act as a stimulant to activate the part of the brain that regulates alertness.
A 2021 study of 80 nurses who worked rotating shifts found rosemary oil aromatherapy helped decrease sleepiness and improved alertness compared to a control treatment.
The study separated the nurses into two equal groups, providing one group with a drop of rosemary oil using a mask (intervention group) and another with a drop of distilled water (controlled group).
The sleepiness mean score in the experimental group decreased from 12.15 to 8.3, while the score for the control group increased from 11.41 to 13.76. There were also increases in alertness scores for the intervention group.
Cognition
Cognition refers to mental processes involved in gaining knowledge and understanding. Some of the cognitive processes are thinking, remembering, and problem-solving. Inhaling rosemary oil may improve these cognitive processes and even reduce the risk of neurological conditions like Alzheimer's disease.
A 2022 Frontiers in Neuroscience report reviewed data on the neuroprotective effects of rosemary oil, finding vast potential benefits on cognitive function and neurological disease prevention. For example, aromatherapy may positively affect cognitive function in older adults. It provides a calming effect on the sympathetic nerves (the nerves that activate a fight-or-flight stress response).
Compounds found in the rosemary plant may help treat and prevent Alzheimer's disease. These include carnosic acid and rosmarinic acid, which are believed to improve memory and learning.
Pain and Inflammation
Rosemary essential oil has anti-inflammatory properties that may help reduce tissue inflammation. Inflammation typically leads to joint pain, swelling, and stiffness.
For example, a 2021 Complementary Therapies in Clinical Practice review of studies found certain essential oils, including rosemary oil, could help with pain management in rheumatic diseases like fibromyalgia, rheumatoid arthritis (RA), and osteoarthritis (OA).
This review included study participants with RA and OA who used lavender, ginger, and rosemary essential oils. Time of use was two to 12 weeks. All 13 studies reviewed, except one, demonstrated the efficacy of aromatherapy for pain management in rheumatic disease.
Cancer-Fighting Properties
One 2020 Nutrients report finds the antitumor effects of rosemary are related to its diverse properties. The report says these include:
Antioxidant effects (helping prevent damage in cells)
Antiangiogenic properties (inhibiting formation of new blood vessels that can feed growing tumors)
Epigenetic actions (altered gene expression)
Regulation of the immune and anti-inflammatory responses
Modification of specific metabolic pathways
Increased expression of onco-suppressor genes (which help prevent cancer formation)
This is because polyphenols in rosemary, including carnosic acid, carnosol, rosmarinic acid, rosmanol, methyl carnosate, and betulinic acid, have anticancer properties. These compounds appear to be effective against the following cancers, among others:
Breast cancer
Ovarian cancer
Prostate cancer
Colorectal cancer
Some rosemary extracts may even boost the effectiveness of chemo and radiation therapies.
While the research is interesting, more research is needed to better understand these effects and how rosemary might be used in cancer prevention or as an adjunct therapy in cancer treatment.
Skin Health
Rosemary essential oil may benefit your skin through its anti-acne properties. It has antibacterial effects that start working as soon as the oil is placed on the skin. It attacks Propionibacterium acnes (an acne-causing bacteria), damaging its cell walls and eventually killing the cells.
Circulation
Poor circulation is a common problem that often affects the hands and feet. If this is something you experience, rosemary oil might help.
In a 2018 study, a 53-year-old woman with Raynaud's syndrome, which impairs blood flow in the hands and feet, used a rosemary blend massage oil to massage her hands for three days and then tried olive oil separately.
She reported that the rosemary blend helped warm her hands more than the olive oil. Thermal imaging showed significant circulation improvement in her fingers when using the rosemary oil but not the olive oil.
More research is needed to confirm the effects of rosemary oil on circulation. But if it helps you, it can be a low-cost option.
Rosemary Oil Side Effects
Rosemary essential oil is considered safe when diluted with a carrier oil and applied to the skin. However, it is possible to experience an allergic reaction.
Aromatherapy with rosemary oil is safe for use in both adults and children over age 3. Limit use around children.
Carrier Oils
Carrier oils dilute essential oils so you can use them safely. They might also help to moisturize and hydrate skin. Argan oil, avocado oil, coconut oil, jojoba oil, olive oil, and sunflower oil are all types of natural carrier oils that are often used for skin care, hair care, cooking, and other uses.
Rosemary leaves are commonly used in food and are considered safe for consumption. However, ingesting rosemary oil is considered unsafe. It is highly concentrated and could lead to allergic reactions. It may also have toxic effects even in small doses.
Rosemary extract, when taken in large amounts, can affect kidney function and cause skin reactions, vomiting, and uterine bleeding. Even so, rosemary extract and essential oil side effects are rare.
Higher doses of rosemary oils and extracts may increase the risk of a miscarriage, especially when consumed rather than used on the skin. Pregnant and nursing people should not use rosemary products without first talking to their healthcare provider. Rosemary leaves are safe when used in small amounts to add aroma and taste to your favorite recipes.
People with certain health conditions—high blood pressure (hypertension), ulcers, and inflammatory bowel disease (IBS)—should avoid taking rosemary internally (other than in cooking uses). With aromatherapy and topical solutions, serious side effects are rare. Still, checking with your health provider if you have any of these conditions before using rosemary essential oil is a good idea.
Rosemary may affect the body's ability to clot and interfere with blood-thinning medicines. Additional medicines that may interact with rosemary include:
Angiotensin converting enzyme (ACE) inhibitors used to treat high blood pressure
Diuretics (water pills)
Lithium used for mood disorders
How to Safely Use Rosemary Essential Oil
Rosemary essential oil may be inhaled or applied topically. It should be used a few drops at a time because it is highly concentrated. If you use it on skin or hair, use a carrier oil to prevent irritation and the oil evaporating too quickly.
Hair
If you want to try rosemary oil to stimulate hair growth, blend a few drops into your shampoo or conditioner. You may also consider mixing several drops of oil with a carrier oil and massage directly into the scalp.
Skin
To use rosemary oil topically, you add it to a carrier oil and apply it to your skin directly. According to the National Association of Holistic Aromatherapy, for a 0.3% dilution, you will want to use no more than 20 drops of essential oil per ounce of carrier oil. You can add a few drops of essential oil to facial oils, skin lotions, creams, or a bath.
Aromatherapy
Adding rosemary essential to an aromatherapy diffuser can distribute the essential oil into the air. You can also simply inhale the rosemary oil by opening the bottle and breathing in its scent in. Another option is to place a few drops on a tissue and hold it near your nose.
Where to Buy Rosemary Essential Oil
You can find rosemary essential oil at your favorite retailer or an herbal store. It is also available to purchase from various online retailers. Rosemary oil is an ingredient in various hair-growth products, shampoos, and scalp treatments, which you can purchase online or in-store.
The Food and Drug Administration (FDA) does not regulate herbal products like essential oils for purity and potency.
When purchasing rosemary essential oil, look for pure and organic products. Check the label to see if the product is 100% pure and undiluted. Avoid oils containing artificial fragrances and other additives to prevent skin irritation and other side effects.
When using essential oils, always follow the product's labeling for dosage and dilution. For topical use, always dilute the essential oil with a carrier oil.
Related: Top 10 Places to Buy Essential Oils
Summary
Rosemary essential oil is versatile with a variety of uses and benefits. Research shows it may boost mood and cognition, ease stress, prevent hair loss, relieve pain and inflammation, and improve circulation.
If you want to use rosemary essential oil, inhale it or apply a diluted version to the skin or hair. When used correctly, side effects are rare. Do not consume essential oils, and follow the product's labeling. Pregnant and breastfeeding people and people with certain health conditions should avoid using rosemary oil without first speaking to their healthcare provider.
When purchasing rosemary essential oil, pick 100% pure and undiluted products. The oil is very concentrated, so you should use a few drops at a time and dilute it with carrier oil if used in hair or on the skin.
Read the original article on Verywell Health.
