Peppermint oil is sometimes too strong for some people. It may induce allergic reactions and other side effects like heartburn and headaches.1 If you're looking for a milder mint oil, look to peppermint's cousin, spearmint (Mentha spicata), also known as the garden spearmint, green mint, fish mint or our lady's mint.2
Spearmint is known for its distinct aroma. It is a favorite in the culinary world, added to dishes and beverages or used as a garnish. The essential oil made from the spearmint herb can also provide a number of important health benefits.
What is spearmint oil?
The use of spearmint dates back to ancient times. This perennial herb originated from the Mediterranean region.3 Ancient Egyptian, Greek and Roman physicians were said to have used it for centuries. It was mentioned by Pliny, the Roman herbalist, in 41 different potions, highlighting its potential as a restorative and for improving digestion.4
In modern times, both the essential oil and the herb itself are widely used as a cure for digestive discomforts like gas and indigestion, as well as for alleviating nausea, cramps and pain.5
Spearmint oil is extracted from the leaves, as well as the flowering tops6 of the spearmint plant. Like other mint family members, it can be identified through its square-shaped stem. The leaves measure 1.5 to 3 centimeters wide (about one-half inch to just over 1 inch) and 5 to 9 centimeters (about 2 inches to 3.5 inches) long. They have pointy tips, just like spears — hence the name.7
There are many who believe that peppermint oil is just too strong and use spearmint oil instead. Although the two oils possess similar properties, spearmint contains lower amounts of menthol compared to peppermint oil.8 No matter your sensitivity, spearmint essential oil is gentler than peppermint oil, especially for children.9
Uses of spearmint oil
The uses of spearmint oil extend beyond the kitchen and the medicine cabinet. For instance, it can be used to help the mind relax or to instill positive emotions. The rejuvenating fragrance is said to help clean the body emotionally and mentally.10 I have compiled a list of spearmint oil's potential uses below:
• Aromatherapy oil — Because of its menthol content, spearmint oil is often used in aromatherapy to help ease fatigue, headaches, migraines, nervousness and even digestive problems.11
• Food ingredient — The oil of spearmint is sometimes added to baked goods, frozen dairy, meats, beverages and candy.12 Note, however, that you are better off consuming whole, raw foods than these processed ones.
• Fragrance — This essential oil is added to certain types of perfume. It is commonly mixed with other herbal oils like jasmine and lavender.13
• Ingredient in dental care products — It is often added to gargles and toothpastes.14
• Pest and insect repellent — This oil can ward off insects like mosquitoes, as well as mice and other rodents.15
Composition of spearmint oil
Spearmint essential oil contains hydrocarbons, alcohols, esters, oxides, and ketones. Its main components include alpha-pinene, beta-pinene, carvone, caryophyllene, linalool, limonene, menthol and myrcene.16 As previously mentioned, spearmint essential oil does not contain as much menthol as peppermint oil. Its primary constituent is carvone, which makes up almost 58 percent of the oil.17
Benefits of spearmint oil
According to a study published in the Journal of Essential Oil Research,18 spearmint oil's antimicrobial properties are obtained from its chemical constituents: cis-carveol and carvone. In studies, it has demonstrated effectiveness against four bacterial strains (Staphylococcus aureus, Escherichia coli, Bacillus subtilis and Pasturella multocida) and fungal pathogens (Aspergillus niger, Mucor mucedo, Fusarium solani, Botryodiplodia theobromae and Rhizopus solani).
Spearmint oil's antimicrobial effects were also shown in another study, published in the Journal of Microbiology Research.19 It highlighted spearmint oil's effect on Bacillus subtilis, Aspergillus niger and Candida albicans. The oil was most potent against Escherichia coli, and also exhibited benefits as an antiseptic and preservative.
How to make spearmint oil
Like other herbal oils, spearmint essential oil is produced through steam distillation — particularly by distilling the leaves or the flowering tops of the plant.20,21 The oil has a pale yellow or olive color, and emits a warm, slightly green and herbaceous scent. Compared to peppermint, it is lighter, sweeter and more spicy.22
How does spearmint oil work?
Spearmint essential oil can be used in a number of ways:23
• Inhalation — Compared to peppermint oil, spearmint oil is milder and can be used around children. Inhaling its fragrance may help fatigue and mental stress.
• Topical application — Add a few drops of this oil to your body care products and it may help ease acne and other skin conditions. Rubbing a diluted solution over your stomach may also ease digestive issues.
• Taken internally — Ingesting spearmint oil can help treat digestive problems. However, this should never be done without the aid of a professional aromatherapist or your physician.
• Added to bath water — This may help relieve fatigue, fever and muscle pain. Make sure to dilute the oil into a carrier oil before adding it to your bath water.24
Is spearmint oil safe?
Like other essential oils, using spearmint undiluted can cause skin sensitivities. It should first be blended with carrier oils like olive oil, almond oil and coconut oil. Using it topically without any carrier oil may cause skin irritations.
To determine if you have sensitivity to any of these herbal oils, apply a drop to a small area of your skin and observe if there are any adverse effects. If you have sensitive skin, it is wise to avoid using essential oils altogether, or to consult a professional before use.
Spearmint oil has a "Generally Recognized as Safe" (GRAS) for ingestion rating from the U.S. Food and Drug Administration (FDA).25 However, it should not be ingested without the advice of an experienced aromatherapy practitioner or your physician.
According to BabyCentre, spearmint oil may be safe to use during pregnancy.26 However, I recommend consulting your physician or an experienced aromatherapist prior to using spearmint oil during this delicate time. Only use a diluted solution.
Side effects of spearmint oil
There are reports of contact dermatitis occurring in sensitive people after using spearmint leaves topically.27 There are also sensitive individuals who were found to have allergic stomatitis and dermatitis to spearmint oil, mainly by using spearmint-flavored toothpaste.28 Hence, it's best to seek the advice of a professional prior to using spearmint oil or any herbal oil.