Wintergreen essential oil is one of the most popular essential oils. It is used in many countries of Europe and North America because of its especially powerful pain-relieving effects. It was known to ancient herbalists that wintergreen has pain relieving effects and that is why they used to apply liniments made from the leaves and twigs for alleviating joint pains. We have come a long way since then. Chemists identified that a unique compound was responsible for its characteristic woody and sweet aroma. This compound was methyl salicylate. It is now used widely as a flavoring agent in food products, gums, toothpastes and mouthwash, although in minute amounts.
Essential oil of wintergreen contains concentrated active volatile constituents. It is used prominently to alleviate joint and muscular pains and sports injuries. But that is not all. It is also a powerful astringent and finds use as a topical agent to treat acne. We shall see some more of the verified medicinal effects of wintergreen essential oil and what sort of safeties to bear in mind while using it.
Many people would have seen the wintergreen shrub. Most commonly used wintergreen is the Gaultheria procumbens. This is the American winterberry, also called as eastern teaberry. It grows naturally as an undergrowth in forests ranging from Nova Scotia to Alabama. Its brilliant scarlet red berries, thick, waxy broad leaves and inverted bell shaped brilliant white flowers are a gardener’s delight. The plant emits a distinct woody and minty aroma. Parts of the plant are eaten by pheasants, red foxes, brown bears and white-tailed deer.
Leaves and twigs of the shrub cannot be used directly to extract essential oil. They have to be fermented for about a week. After this, essential oil is extracted by steam distillation. For certain medicinal purposes, essential oils are extracted using methanol as solvent.
Two other species of wintergreen are also used to produce medicinal grade essential oil. One of them comes from India and Nepal, called Gaultheria fragrantissima. The other one, G. yunnanens comes from Yunnan province in China.
Color and Aroma
Wintergreen essential oil has a distinctive pinkish yellow color which is quite unlike the color of most other essential oils. It has a sharp minty and woody aroma with hints of pine. One can also discern a sweet, fruity top note on top of the woody scent.
The aroma of wintergreen essential oil is much more complex and multi-faceted when compared with that of methyl salicylate. Although methyl salicylate forms about 96% of the oil, it is not the complete oil. Other volatile compounds, even in minor amounts, bring their aromas and therapeutic effects to the table.
- Anti-Inflammatory – It has a potent anti-inflammatory effect which is not only due to methyl salicylate but also contributed to by other compounds like gaultherin, alpha-pinene and myrcene. 
- Analgesic – Wintergreen oil exerts pain relieving effects when applied topically. 
- Astringent – When applied on the skin, it shrinks up the pores, leading to a toning effect. 
- Carminative – Its aroma helps to expel built up intestinal gas via flatulence. 
- Diuretic – It increases the production of urine temporarily, possibly via a detoxification mechanism. 
- Emmenagogue – The herb and its essential oil have been known to improve menstrual flow by increasing local blood circulation of the pelvic region and the uterus. 
- Galactagogue – It naturally improves production of mother’s milk. 
- Antibacterial – yunnanens has been found to inhibit Staphylococcus aureus and E. coli bacteria. 
- Rubefacient – It improves local blood circulation and causes redness, which is what a rubefacient does. This effect is mainly due to methyl salicylate.
Health Benefits and Uses
Against Joint Pain
Oil of wintergreen is used as a topical agent against painful joints. It works against active conditions but is also useful in relieving pain caused by chronic conditions like gout and arthritis. Essential oils of wintergreen and peppermint (from Mentha piperita) should be used in combination against joint pain. Together, they can give pain relief that is comparable to capsaicin (which comes from cayenne pepper) or commonly used NSAID drugs like ibuprofen. One can make a liniment at home using just a few ingredients.
10 drops each of essential oil of wintergreen and peppermint should be added to 100 ml of coconut oil or grapeseed oil as a base. Keep this mixture in an amber tinted glass bottle. Shake it slowly so that essential oils are uniformly dissolved. Few drops of this mixture should be poured onto a cotton cloth and applied directly onto the painful joint. It is not advisable to put this mixture onto the palm and then applying it onto the joint. Both wintergreen and peppermint are quite pungent and if you mistakenly touch your eyes, it will hurt bad and can be dangerous for the eyes.
The essential oil based liniment should be rubbed into the joint for about 10 minutes and left as is. As time passes, they provide steady relief from pain. But in case of pain caused by a chronic condition, the pain eventually returns. At best, wintergreen oil can help to deal with the pain.
Active chemicals from wintergreen and peppermint enter our blood through their skin. The base oil helps in carrying these active constituents by properly diluting them and carrying them into the blood stream. The exact mechanism of anti-inflammatory and analgesic effect of wintergreen oil is not known, however we do have some preliminary concepts.
Firstly, wintergreen and peppermint essential oils are modulators of TRP channels. These are protein based signalling mechanisms used by us humans and other animals to detect chemicals in our environment. Peppermint mainly contains menthol, which feels cooling on the skin because it activates a TRP channel. By this mechanism, these essential oils act as counter irritants. They create a mild burning, warming and stinging sensation which has a role to play in reducing joint pains.
Secondly, essential oils may be increasing blood circulation to the joints. The blood brings with itself nutrients and pain-relieving chemicals that are released by our hormonal system in response to the signals of pain that are sent to our brain.
Thirdly and this is where wintergreen oil assumes prominence, the methyl salicylate may be causing anti-inflammatory effect similar to the one produced by aspirin. Methyl salicylate closely resembles aspirin in chemical structure. Methyl salicylate may be having an effect in reducing inflammatory prostaglandins by inhibiting cyclo-oxygenase enzymes within our body. This is the way in which NSAID medicines works. Such a deeper anti-inflammatory effect would explain how wintergreen oil is not just effective in sprains and muscular aches, but also in the more serious rheumatoid arthritis.
Note of Caution – Wintergreen oil’s methyl salicylate gets metabolized in our body into aspirin. So, when we are applying wintergreen oil on the skin, it is akin to taking a dosage of aspirin. We know that aspirin is an essential life saving drug. But if it exceeds the recommended amount, it can be lethal. We are using 10 drops of wintergreen oil in 100 ml of oil, which comes out to be about 0.5% volume by volume (v/v).
Wintergreen Oil for Acne
Wintergreen oil is used to reduce excess oil on the face and to shrink down the pores. Add 5 drops of wintergreen essential oil to 100ml of jojoba oil. Mix it thoroughly and store it safely. This mixture should be applied wherever breakouts are prominent. Acne pimples commonly emerge in clusters at the forehead, cheeks, back of the neck, upper back and near the jawline. Use a cotton ball to apply the oil evenly on the affected regions. It would sting and create redness and a burning sensation because of its menthol like pungent nature. Pores get shrunk and skin feels tighter.
Wintergreen oil’s effect would be similar to salicylic acid based face wash that are commonly prescribed by dermatologists to reduce oiliness on the face and to shrink the pores. However, essential oil has a much higher anti-inflammatory effect because of its many active phytochemicals.
Word of caution – In some people with sensitive skin, wintergreen oil can cause so much of a burning sensation that it can actually aggravate acne. This happens because of strong counter-irritant effects. You would notice much more redness and pain, especially if you suffer from cystic acne. There is also the risk of acne getting transformed into thick scars which are even more difficult to treat once the acne naturally diminishes. It is always prudent to do a patch test of the diluted essential oil on the forearm to check for sensitivity and any possible allergic reactions.
Its aroma has a stimulant effect. It seems to bring calm to some people which is caused by a reduction in stress or anxiety, but this effect is not universal. Its woody, pine like cool aroma gives off an enchanting vibe. If the diffusion is too strong, it may cause a burning sensation. It begins to exert a diuretic effect which would cause you to urinate more than you would regularly. Its aroma gives relief from bloating and the resulting abdominal distension due to its carminative effect.
Besides these, wintergreen oil is not very popular in aromatherapy. Due to its astronomically high concentrations of methyl salicylate, its safety in aromatherapy blends is questionable.
Wintergreen oil for Hair
Although wintergreen oil and methyl salicylates are used in hair regeneration products, there is no credible evidence to suggest that it actually works for alopecia. Some other firms use methyl salicylate for its aroma in shampoos and conditioners. But, methyl salicylate acts as an irritant on the scalp, just as menthol does. It feels numbing and cooling. It does shrink pores though, which might lead to a stronger hold of the pores on hair follicles. However, this is not known with certainty. Peppermint essential oil, on the other hand, has been proven to help with hair regeneration in case of alopecia. What is even more noteworthy is that while wintergreen oil is toxic due to its aspirin like effects, peppermint oil’s usage on the scalp leads to zero toxicity. 
There is also no evidence to suggest that wintergreen oil helps to get rid off dandruff. In my opinion, weighing in the facts about its side effects and lack of enough evidence to suggest benefits for hair, it is not advisable to use wintergreen oil for haircare.
Analysis of chemical constituents of wintergreen oils from different species of wintergreen has revealed that they universally have very high levels of methyl salicylate. American wintergreen can have 97% methyl salicylate on average; the concentration of methyl salicylate reaches up to a staggering 99.7% of Indian wintergreen oil. One would assume that the oil is all the same as methyl salicylate. But that would be erroneous. The remaining 0.3 to 3% of oil contains minute amounts of volatile compounds that are active, like monoterpenes and sesquiterpenes. We can detect them in aromas too.
In the table below, chemical composition of essential oil of Indian wintergreen (Gaultheria fragrantissima) sourced from the foothills of Himalayas in Nepal is mentioned.
|Volatile compound||Type||Concentration (as percentage)|
Alpha pinene is useful as a bronchodilator. It opens the airways and provides relief from congestion that we experience in asthma, bronchitis and infectious diseases of the respiratory tract.  It is absorbed readily by our respiratory system, and from there it reaches the blood, where it activates powerful anti-inflammatory channels. Alpha pinene is reminiscent of pines. Its aroma induces calm and boosts memory. However, in case of asthma and respiratory infections, other essential oils like those of sweet anise, eucalyptus and tea tree oil are more applicable.
Limonene is the chief volatile responsible for tangy, citrusy aroma of citrus essential oils. Its aroma acts as a powerful relaxant. It has been verified in clinical research that limonene can neutralize excess acidity in our gastric acid secretions. This way, it provides relief in GERD. 
Myrcene reduces the risk of peptic ulcers. Together with limonene, it may be exerting a synergistic effect. Some people have reported that wintergreen oil helps with ulcers. This could very well be attributed to myrcene and limonene. Myrcene also exerts cartilage protection effects.  Cartilage is the smooth and elastic rubber like protective tissue that exists at the ends of bones to enable frictionless movement of the joints. It would be wrong to assume that methyl salicylate is the only active pain-relieving compound from wintergreen oil that works against joint pain. Myrcene, despite its minute concentration, would also be playing a role in fostering better joint health to enhance mobility.
The anti-inflammatory, analgesic and rubefacient effect of methyl salicylate are well known. However, it is important to be informed about its potential toxicity to humans.
Side Effects and Toxicity Issues
Methyl salicylate is a known skin irritant, even at low doses of 1% in formulations. Since wintergreen oil is dominated by methyl salicylate, the side effects of both would be almost similar. Wintergreen oil is equally toxic. It has potential to cause skin irritation.
Essential oil of wintergreen should never be ingested. Even in minute amounts, it can cause allergic reaction. There is a confirmed case of swelling of the larynx in a person who accidentally ingested the essential oil.  It should be kept far away from reach of infants and kids, because it is fatal to them.
Topical application of wintergreen oil requires caution. Methyl salicylate gets absorbed into our body through the pores of our skin. Inside our body, it mimics aspirin.
5 ml of pure wintergreen essential oil is equivalent to 7000 mg of salicylate, which is equal to 21.7 aspirin tablets. This is a staggering number.
20 drops from a regular essential oil dropper make up 1 ml. We have advised a formulation which uses 5 drops of wintergreen oil in 100ml of base oil, which turns out to 350 mg of salicylate. Even this amount is significant, because a regular tablet of aspirin contains 322.5 mg of salicylate.  However, at this concentration, it would not lead to toxic effects in an otherwise healthy adult person.
Aspirin, as we know, is a potent blood thinner. It is prescribed not just to alleviate pain, but also in cases of heart attacks to lower the risk of death. It interferes with blood thinners. People who are on blood thinners should not use wintergreen essential oil. It should also be avoided by people who suffer from hypertension or any kind of heart disease. Wintergreen essential oil should not be used by pregnant women. People suffering from asthma should avoid it too, because it may act as a respiratory irritant. 
Methyl salicylate can cause abnormal deliveries and low birth babies in women who use it. In a study on rats, its usage even led to birth defects in rat offspring. It had a particularly damaging effect on the development of kidneys of offspring. This means that there could be possible harmful effects of methyl salicylate (and therefore, of wintergreen oil) on the functioning of kidneys. 
Wintergreen essential oil is only helpful in minor injuries, aches, cramps, sprains and strains. If you have suffered from any major cut, bruise or serious injury to the muscle, tissues or bones, it should not be used. In such a case of serious injury, hospital care is advised.
Do not attempt to use wintergreen essential oil in aromatherapy blends because the safety of such blends is not evaluated. You may end up creating something that is toxic and dangerous to health.
Buying and Storage
When buying wintergreen oil, one must be cautious. There are many fraudulent sellers trying to pass off methyl salicylate made in some lab as pure essential oil of wintergreen. As we have seen earlier, although methyl salicylate forms the dominant volatile in the essential oil, the contribution of other compounds in minor amounts is also significant. Together they make up the complete wintergreen essential oil. Be sure to check the product for the name of the species from which it is distilled, its chemical composition, method of use and safety instructions.
Best container to store essential oil is thick, amber tinted glass which is to be placed in a cool location away from direct sunlight. It has a poor shelf life, so there is wisdom in buying smaller volumes each time.
- Gaultheria: Phytochemical and Pharmacological Characteristics. Wei-Ru Liu et al, Molecules. 2013 Oct; 18(10): 12071–12108
- Peppermint Oil Promotes Hair Growth without Toxic Signs. Ji Young Oh et al, Toxicological Research.
- Parsley Essential Oil – OilHealthBenefits.com
- Grapefruit Essential Oil – OilHealthBenefits.com
- Evaluation of the anti-inflammatory, anti-catabolic and pro-anabolic effects of E-caryophyllene, myrcene and limonene in a cell model of osteoarthritis. Rufino A.T. et al, Eur J Pharmacol. 2015 Mar 5;750:141-50.
- Laryngeal oedema caused by accidental ingestion of Oil of Wintergreen. Botma M. et al, Int J Pediatr Otorhinolaryngol. 2001 May 11;58(3):229-32.
- Methyl Salicylate-Menthol Ointment. WebMD.
- Risk profile – Methyl Salicylate, mattilsynet.no