(INCLUDING A PERSONAL EXPERIENCE AS RELATED TO SUSPECTED SARSCoV2 VIRAL INFECTION)
What are Essential Oils?
As so eloquently written by Valerie Ann Worwood, 2000, “Essential oils are one of the great untapped resources of the world. Here we have a system of natural help that is far more than a system of medicine that can prevent illness and alleviate symptoms. These extremely complex precious liquids are extracted from particular species of plant life and are in harmony with people and the planet alike. By taking essential oils into our lives, we find a way to provide our family and home with the protection and pleasure they need without polluting ourselves or our environment with chemicals. These days the medicines and household goods we use are mostly chemical-based, and the food we eat and the air we breathe contain more chemicals than we would like. The cumulative effect of these, and the unknown effects as they react together within us, cannot be good for us, any more than chemical overload is good for the planet.” 
When people think of essential oils, many may think of them only as aromatics. In mainstream use, they create pleasantly scented homes while providing those around their vapours with an enjoyable feeling. But an essential oil of high quality and therapeutic grade can bring balance back into the body. As mentioned in the Essential Oils Reference, Sixth Edition, in historical times dating back to 4500 BC, the ancient Egyptians utilized plants and essential oils to successfully support healing and overall wellness.
Essential oils are distilled from the fluid inside the plant, which functions as the plant’s defence system. These fluids are necessary for regenerating, oxygenating, and strengthening the immune abilities of plants and are essential for plants’ survival. The microscopic molecules found in essential oils can penetrate the plant cells and thereby stimulate their natural healing process. Much like in the ways that a plant can heal itself from within when plant fluids are distilled and extracted, and when used topically, aromatically, or internally, these essential oils can help balance each system in the human body.
What is the Olfactory System?
The olfactory system includes the nose, nares, nasal cavities, and olfactory nerves. The upper sections support the mucous membrane for the perception of smell, and the lower areas act as respiratory passages. As described online by Encyclopedia Britannica (2021), the olfactory nerve is unique compared with all other cranial nerves. It has the inherent ability to regenerate and likely will regenerate throughout our lifetime. This may be promising for those who experience the loss of smell.
What is the Respiratory System?
The respiratory system comprises of two systems: the upper respiratory system (what many think of like the nose and sinuses, but also includes the pharynx and oral cavity) and the lower respiratory system, which consists of the larynx, trachea, bronchi, bronchioles, lungs, diaphragm and thorax. The respiratory system is involved in the intake and exchange of oxygen and carbon dioxide.
As also described by Encyclopedia Britannica on the internet (2021), for respiration to occur, other organ systems’ collaboration is vital. With the control of the central nervous system, the diaphragm is in charge of the pumping action on the lungs. The muscles expand and contract in the thorax, and the lungs and chest wall (ribs and muscles) accomplish respiration.
What is Loss of Smell?
Anosmia is the medical term used when a person loses the sense of smell. Loss of smell can be caused by infection, trauma, or idiopathic reason, meaning there is no definitive cause. A simple Internet search reveals that some causes that contribute to loss of smell include, but are not limited to, cancer, Parkinson’s Disease, tumour, aneurysm, stroke, allergies, toxins, or viral infections like seasonal flu.
Nowadays, infection from the most recently discovered coronavirus, SARSCoV2, which can lead to Covid-19, is one of the main culprits as to why so many people are losing their sense of smell. The CDC lists “new loss smell or taste” as one of the main symptoms of SARSCoV2. The average number of days related to loss of smell varies among sources, ranging from eight days to six weeks and beyond. According to a review conducted by Zahra et al., as of November 2020, anosmia and dysgeusia were frequently reported in SARSCoV2 patients.
What is Olfactory Training?
Olfactory Training (OT), also known as Smell Training or Smell Therapy, is an underutilized therapeutic approach in helping those who have lost their sense of smell. Many physicians are unable to help their patients who have had anosmia. A typical course of treatment involves the use of steroids, which are minimally effective for patients. If steroids do not help, doctors generally have no other solution to offer. OT entails having patients perform repetitive and scheduled inhaling of different odorants over a long period. Aromas from diverse categories, such as floral, fruity, and resinous, are significant. Patients are instructed to focus on what they smell during this protocol. Most protocols have patients sniffing these odours at least twice a day, and the duration may vary from 12 to 56 weeks.
In one 2009 study conducted by Hummel et al., 40 patients completed training with different odours over 12 weeks. The scents used were rose, eucalyptus, lemon and clove (no botanical names given in this study), and the patients used Aroma sticks twice a day. Compared to other patients who did not engage in the training, the results for patients who performed the structured, short-term exposure seemed to increase olfactory sensitivity, regaining some sense of smell. 
In a 2014 study conducted by Konstantinidis et al., the scientists evaluated two groups of patients (119 in all four groups) for their sense of smell. Over 16 weeks, the researchers compared them to two control groups with similar diagnoses. Four odours were chosen (rose, eucalyptus, lemon and clove; no botanical names used). Testing was conducted with Aroma sticks twice a day (Aroma sticks were developed decades ago and are still a standard for many smell training programs). The results at both eight weeks and 16 weeks showed that the patients who utilized OT performed significantly higher than both of the control groups without OT.
In a more recent study published in January 2021 by Serge-Daniel et al., similar results have been observed. The study chose 72 subjects confirmed positive for COVID-19, non-hospitalized, and with the sudden loss of smell. On average, these patients were identified about five weeks after losing their sense of smell. Of this group, only 27 subjects participated in the treatment. The researchers divided them into two groups: one group of nine was treated with both a 10-day corticosteroid and OT course. The other group of 18 participants was treated with OT only. According to the results of this study, only the patients who received the combination therapy had “significantly improved” their sense of smell.
There is a variety of research on which odours seem to be the most beneficial for OT. Still, most sources suggest cinnamon leaf (Cinnamomum zeylanicum), clove (Syzygium aromaticum), eucalyptus (Eucalyptus radiata), lemon (Citrus limon), rosemary (Rosmarinus officinalis), which is also great for memory, and rose (Rosa damascena).
For my personal experience, because of their distinctly potent, familiar scents as well as for the wide range of constituents found in these oils to help stimulate the entire olfactory system, I chose the following oils: eucalyptus (Eucalyptus radiata), lime (Citrus aurantifolia), patchouli (Pogostemon cablin), peppermint (Mentha x piperita), rose (Rosa damascena), rosemary (Rosmarinus officinalis), thyme (Thymus vulgaris), and wintergreen (Gaultheria procumbens). Additionally, the oils selected also help stimulate the respiratory and immune system, which could also help support the body during active viral infection.
Essential Oils and Their Constituents
Based on the constituents I selected the following essential oils:
- Eucalyptus (Eucalyptus radiata): Rich in the oxide eucalyptol, responsible for eucalyptus’s familiar and intensive scent. Oils high in oxides are great for the respiratory system and have anti-inflammatory and antiviral properties.
- Lime (Citrus auranifolia): Similar to lemon (Citrus limon), lime is high in limonene, terpinene, and pinene, which are antiviral and antibacterial. Lime has historically been used for supporting and strengthening the respiratory and immune systems.
- Patchouli (Pogostemon cablin): Rich in sesquiterpenes, which have a broad spectrum of action and are more aromatic, have anti-inflammatory and immune-stimulating. In mainstream use, patchouli is well known for its earthy aroma.
- Peppermint (Mentha x piperita): Rich in monoterpenols, which have anti-inflammatory, anti-spasmodic, and immune-stimulant properties. Monoterpenols soothe the nervous system.
- Rose (Rosa damascena): High in oxides, which conceivably have the most assertive aroma, gives rose its strong, signature scent. Several oils that have expectorant and decongestant properties and are antiviral and anti-inflammatory contain oxides.
- Rosemary (Rosmarinus officinalis): Rich in the oxide 1,8-cineole (syn. eucalyptol), giving rosemary its distinctive aroma. Rosemary is also rich in camphor, which behaves as a stimulant and is good for pulmonary congestion, and is also high in verbenone, which is regenerative.
- Thyme (Thymus vulgaris): has two helpful phenol chemotypes for stimulating the immune system. CT thymol has anti-inflammatory properties, and CT linalool has anti-infectious and antitussive actions. Thyme has a robust, spicy aroma like the plant’s aroma.
- Wintergreen (Gaultheria procumbens): Rich in esters known for their anti-inflammatory and calming properties. Wintergreen has a memorable cool, crisp, minty scent.
A PERSONAL EXPERIENCE
Method of Application: I used direct inhalation of each essential oil via its essential oil bottle. I inhaled them for five-ten seconds at a time, two to three times a day (morning, afternoon, and evening), focusing on remembering what the scent smelled like. Cognizant of taking a five-second break between each essential oil, I repeated the process with subsequent essential oils.
History: I am a female, almost 44 years of age at the time of illness, with weight in the upper ends of ordinary for height and age. I exercise 3-4 times a week and sleep well, easily fall asleep without assistance and stay asleep for 7-10 hours (generally between 9:00-11:00 pm through 5:30-7:30 am), needing to use the bathroom on average once in the early morning hours. Overall, I consider my diet healthy with daily servings of fruits and vegetables, whole grains (gluten-free), and animal and plant-based proteins (dairy-free options except cheese and chocolate). My water intake is likely on the low end of every day to below average, and my caffeine intake is on the higher end of normal.
Illness: During my studies, I contracted what would appear to be SARSCoV2, self-described as mild severity. I did not get tested for Covid-19 as I efficiently managed my symptoms at home, but I observed the characteristic ‘new loss of smell’. A progression of the illness for 14 days, as well as implementing OT as a way to improve loss of smell, is as follows:
Day 1: I woke at 2 am feeling well-rested but surprised it was early in the morning. Shortly after waking, I began feeling ill with a massive headache similar to a migraine but more intense. I experienced chills on and off for 5 hours with tender hips and restless legs, which needs stretching to find relief. I dozed off and on between 3 am-7 am, finally falling back to uninterrupted sleep from about 7 am-10 am. I awoke with a severe headache and a very mild, intermittent, dry cough. After attempting topical use of essential oils to support my neurological system for migraine symptoms, I took 400mg Ibuprofen and my headache was relieved entirely.
I used a variety of respiratory supporting essential oils [singles or blends with eucalyptus (Eucalyptus radiata), rosemary (Rosmarinus officinalis), frankincense (Boswellia carterii), lemon (Citrus limon), cinnamon bark (Cinnamomum zeylanicum), and clove (Syzygium aromaticum) both topically following the recommended dilution ratios for adults, as well as diffused throughout the day. I increased my oral intake of Vitamins C, B Complex, K2 D3, zinc, and a liquid antioxidant supplement and introduced homoeopathic medicine and increased my use of essential oils to support my immune system.
The rest of the day, no other telltale symptoms of illness such as fever, chills, GI issues, etc., showed. My appetite was normal, my food intake was typical, and I fell asleep soundly from about 6 pm-7 am the following day.
Day 2: Upon waking, I had a severe headache and a mild, intermittent dry cough. After again attempting essential oils to support my neurological system proved unsuccessful. I took 400mg of Ibuprofen, and the headache wholly seized.
I used respiratory-supporting essential oils both topically (following recommended dilution ratios for an adult) as well as diffused throughout the day. I continued with an increased oral regimen of Vitamins C, B Complex, K2 D3, zinc, antioxidants, homoeopathic medicine, and essential oils to help support my immune system.
In the afternoon, I experienced mild brain fog, but I remained awake, alert, and active until 10:30 pm. I did notice that my appetite decreased, which resulted in less eating for the day, but with an increase in fluid intake via water and teas. I attained a restful sleep from 10:30 pm-7 am.
Day 3: Upon waking, I observed that no headache was present. I had a mild, intermittent dry cough throughout the day with a slight increase of mucus/postnasal drip with occasional productive cough.
I continued using respiratory-supporting essential oils both topically and aromatically. I also continued with increased oral intake of Vitamins C, B Complex, K2 D3, zinc, antioxidants, homoeopathic medicine, as well continued use of essential oils throughout the day to support my immune system.
I noticed that the brain fog has increased in the afternoon and evening, but it did not interfere with my typical daily tasks. I was able to remain awake, alert, and active. I also noticed that my appetite returned to normal, and I ate as usual throughout the day and continued with increased fluids. I attained restful sleep from 9:40 pm-7:10 am.
Day 4: I woke with some slight congestion in my ears and sinuses, with clear mucous blowing my nose and a productive cough. Midday, I experienced gastrointestinal upset. It was very likely due to the increased ingestion of high doses of Vitamin C. While washing my hands with a fragrant essential oil-infused soap, I suddenly observed some loss of smell described as if a “puff of smoke took away the smell.” Immediately I went to smell a variety of essential oils (citruses, spices, florals, and camphoraceous), and each scent was very faint.
Despite my diminishing sense of smell, I continued to use various respiratory-supporting essential oils topically and diffused throughout the day. I also continued with oral intake of Vitamins C, B Complex, K2, D3, zinc, antioxidants, homoeopathic medicine, and using essential oils throughout the day to support my immune system.
There was noticeable brain fog in the afternoon and evening, but it did not interfere with my daily tasks. My appetite and food and liquid consumption were typical. I remained awake, alert, and active until dozing between 9:30 pm-11 pm. When I awoke at 11 pm, I increased moderate, intermittent coughing for about 30 minutes. After I reapplied essential oils, I slept well until 6:30 am.
Day 5: Upon waking, my coughing increased on/off with some productivity, brain fog was noticeable throughout the day, and I had a very vague sense of smell for all scents attempted.
I began formal OT using rosemary (Rosmarinus officinalis), eucalyptus Eucalyptus radiata), patchouli (Pogostemon cablin), peppermint (Mentha x piperita), and lime (Citrus auranifolia). I inhaled each of these essential oils three times throughout the day, noting a very faint smell for rosemary (Rosmarinus officinalis) only.
I continued to use essential oils for supporting my respiratory system per usual throughout the day and continued with oral regimens of Vitamin C, B Complex, K2 D3, zinc, antioxidants, homoeopathic medicine, and essential oils to support my immune system. I ate typically and slept soundly from 10 pm-7 am.
Day 6: I woke up feeling refreshed but with an increase in cough and congestion (stuffy nose, full ears, runny nose), and brain fog was still noticeable late afternoon.
I observed a complete loss of smell for all scents. I performed OT three times per day, using thyme (Thymus vulgaris), rose (Rosa damascena), and wintergreen (Gaultheria procumbens) in the rotation, not being able to recall any of the familiar scents.
I continued using respiratory-supporting essential oils topically and aromatically. I also continued with my oral regimen of Vitamin C, B Complex, K2 D3, zinc, antioxidants, homoeopathic medicine, and essential oils to support my immune system. My appetite was as usual, and I slept great from 10:30-7 am.
Day 7: I woke with a productive cough first thing in the morning and then intermittent moderate coughing throughout the day. Complete loss of smell was evident, and a mild-moderate decrease in the ability to taste; however, salty, sweet, and sour tastes seemed intact.
I continued using respiratory-supporting essential oils topically and aromatically throughout the day. I continued my Vitamins C, B Complex, K2 D3, zinc, antioxidants, homoeopathic medicine, and essential oils to support my immune system. Despite the decrease in tastes, I ate as normal. I slept well from 10:30-7 am, as typical for my habits.
Day 8: I awoke with thicker mucous and an increase in productive cough first thing in the morning, noting mild-moderate coughing throughout the day. I began using a Neti Pot to help successfully expel mucous from my nasopharyngeal area.
I continued to experience a complete loss of smell, still with a faint taste for most foods and flavours. I went on with OT three times over the day using rosemary (Rosmarinus officinalis), eucalyptus (Eucalyptus radiata), patchouli (Pogostemon cablin), peppermint (Mentha x piperita), rose (Rosa damascena), thyme (Thymus vulgaris), wintergreen (Gaultheria procumbens) and lime (Citrus auranifolia). None of the familiar aromas yet recovered.
Intensification in brain fog was apparent to me; thus, I increased vitamins and supplements by one additional serving to help support my neurological system. Overall my appetite, fluid and food intake, as well as sleep, were normal.
Day 9: Again, I awoke with thicker mucous and moderate coughing throughout the day. I used a Neti Pot twice to assist with expelling mucous. I continued to observe a complete loss of smell and faint taste. I continued with OT three times a day using all essential oils selected in the protocol, not yet recovering any scents.
I continued using respiratory supporting essential oils topically and diffused throughout the day. I continued with Vitamins C, B Complex, K2, D3, zinc, antioxidants, homoeopathic medicine orally, as well as using essential oils per routine to support my immune system. I ate well throughout the day and slept from 12:15 am-7:00 am, given the New Year’s holiday.
Day 10: I woke and presented with thinner mucous and mild-moderate coughing throughout the day and continued to use Neti Pot twice a day to help expel the mucous.
Upon initial OT in the morning, I faintly smelt rosemary (Rosmarinus officinalis), eucalyptus (Eucalyptus radiata) and peppermint (Mentha x piperita); however, I did notice a slightly putrid scent to peppermint. Per other studies, it appears that when the sense of smell returns, there is a period when aromas do not return with their pleasant or familiar scent. With the subtle increase in smells returning, some faint tastes were also resuming. I performed OT two additional times throughout the day/evening using the aroma selected for OT protocol. Notes for these essential oils were becoming slightly stronger by day’s end.
I continued using respiratory supporting essential oils, taking Vitamins C, B Complex, K2 D3, zinc, antioxidants, homoeopathic medicine orally, and using essential oils to support my immune system as I have been thus far. I ate meals as usual and slept soundly from 10 pm-6:30 am.
Day 11: Upon waking, I had less congestion and coughing and discontinued the use of Neti Pot. I lightly started smelling the targeted essential oils during OT with a less putrid smell noted with peppermint (Mentha x piperita).
As I continued observing brain fog despite a restful slumber, I added one additional serving of vitamins and supplements to support my body.
OT yielded improved scent recognition for several oils. In the morning, I was able to faintly recall the aroma in an essential oil-infused hand soap, in which included cinnamon bark (Cinnamomum zeylanicum), sweet orange (Citrus sinensis), black spruce (Picea mariana), as well as began to more subtly recall scents for rosemary (Rosmarinus officinalis), peppermint (Mentha x piperita), and lime (Citrus auranifolia) essential oils.
I noted increased coughing midday, but I could alleviate/suppress the coughing for one hour while soaking in Epsom Salt bath with lavender (Lavandula angustifolia) and eucalyptus (Eucalyptus radiata). I continued using essential oils to support my respiratory system and continued with my regimen of Vitamins C, B Complex, K2 D3, zinc, antioxidants, homoeopathic medicine, and essential oils to help my immune system. I ate normally, drank as typical, and slept soundly from 10 pm-7 am.
Day 12: I noted improvement in my upper respiratory system as my runny nose began to subside, my coughing significantly reduced, and a significant decrease in brain fog was evident.
It was exciting to observe that scents were returning more robustly first thing in the morning. I was able to distinctly recall smells for rosemary (Rosmarinus officinalis), peppermint (Mentha x piperita), lime (Citrus auranifolia), and began sensing odours for other essential oils used during OT. In the afternoon, I smelled bacon, which was the first non-essential oil smell to have returned. I continued OT two additional times throughout the day with the same scents able to be elicited in the morning.
I continued to use essential oils topically and diffused throughout the day for both respiratory and immune support. I continued taking my Vitamins C, B Complex, K2, D3, zinc, antioxidants, homoeopathic medicine. I ate and drank as typical and slept well from 10 pm-6 am.
Day 13: I noted improvement of scents as I was able to smell peppermint (Mentha x piperita), eucalyptus (Eucalyptus radiata), lime (Citrus auranifolia), thyme (Thymus vulgaris), rosemary (Rosmarinus officinalis), and wintergreen (Gaultheria procumbens). I was not yet able to recall patchouli (Pogostemon cablin) or rose (Rosa damascena).
I experienced moderate coughing throughout the day and used respiratory supporting essential oils as standard during this time. I also continued oral administration of Vitamins C, B Complex, K2, D3, zinc, antioxidants, homoeopathic medicine, and essential oils to support my immune system. I ate meals as typical and slept peacefully from 10 pm-6:45 am.
Day 14: According to the CDC guidelines, it appears that SARSCoV2, when mild, generally runs its course within 14 days, and those with the infection are no longer contagious. While I continued informal OT throughout the month “for good measure”, I concluded with formal data collection after this day.
I experienced mild-moderate intermittent dry coughing throughout the day. I used respiratory supporting essential oils aromatically and topically per usual, and OT continued three times throughout the day. I was able to recognize eucalyptus (Eucalyptus radiata) and eucalyptus (Eucalyptus globulus), peppermint (Mentha x piperita), lime (Citrus auranifolia), thyme (Thymus vulgaris), patchouli (Pogostemon cablin), rose (Rosa damascena), and wintergreen (Gaultheria procumbens).
As I recalled more scents, I introduced the following favourite blends with success noted:
- Blend 1: Eucalyptus (Eucalyptus globulus), myrtle (Myrtus communis), marjoram (Origanum majorana), pine (Pinus sylvestris), eucalyptus (Eucalyptus radiata), lemon eucalyptus (Eucalyptus citriodora), lavender (Lavendula angustifolia), cypress (Cupressus semprevirens), black spruce (Picea mariana), peppermint (Mentha x piperita)
- Blend 2: White camphor (Cinnamomum camphora), lemon (Citrus limon), wintergreen (Gaultheria procumbens), peppermint (Mentha x piperita), eucalyptus (Eucalyptus radiata)
- Blend 3: Clove (Syzygium aromaticum), lemon (Citrus limon), cinnamon bark (Cinnamomum zeylanicum), eucalyptus (Eucalyptus radiata), rosemary (Rosmarinus officinalis)
- Blend 4: Bergamot (Citrus bergamia), ylang ylang (Cananga odorata), geranium (Pelargonium graveolens), lemon (Citrus limon), coriander (Coriandrum sativum), tangerine (Citrus reticulata), jasmine absolute (Jasminum officinale), roman chamomile (Chamaemelum nobile), palmarosa (Cymbopogon martinii), rose (Rosa damascena)
- Blend 5: Balsam Canada (Abies balsamea), coriander (Coriandrum sativum), bergamot (Citrus bergamia), frankincense (Boswellia carterii), Idaho blue spruce (Picea pungens), ylang ylang (Cananga odorata), geranium (Pelargonium graveolens)
I continued taking Vitamins C, B Complex, K2 D3, zinc, antioxidants, homoeopathic medicine, and essential oils orally to support my immune system. I ate as usual and slept from 10:45 pm-7:10 am. At this point, I stopped the formal data collection for Olfactory Training.
Summary and Conclusion
I began to feel the symptoms of a viral infection, assuming it to be SARSCoV2 as noted by severe headache, joint and muscle discomfort, some on/off again chills in the early morning hours, despite not knowingly having been around anyone with the virus. A very mild, intermittent dry cough began on Day 2, which remained steady for five days and progressing to a more consistent cough throughout the day, moving from dry cough to productive cough. I abruptly noted my loss of smell on Day 4, with complete loss of smell by Day 6, and formal implementation of OT began on Day 5.
In terms of the effects of OT, my ability to smell a variety of scents started to return faintly on Day 10 (five days later) and returned almost entirely by Day 14. At this point, I introduced additional single essential oils and blends with the ability to smell all of them. I ceased formal data collection after Day 14. However, informal, anecdotal observation showed that by 30 days post-infection, the sense of smell had almost completely returned to normal for various scents and different aroma notes. There was a residual, mild dry cough first thing in the morning, late at night after dinner, and occasional coughing when triggered by outdoor cold air or laughing. By day 60, all scents had returned to normal and lingering mild; the intermittent cough had ceased altogether.
It is worth noting that almost a year ago, I had experienced a very similar viral respiratory infection with significant coughing that seemed identical to this year’s bout but more compromising on the respiratory system. I wonder if last year I had a mild case of pneumonia or “walking pneumonia” was present. This year’s infection seemed less severe, and I was able to better manage it with increased vitamins (I did not use vitamin therapy last year), supplements (I was not as diligent the previous year), essential oils, and homoeopathy. A new symptom noted this year was the loss of smell, which has never happened to me before. I would conclude with confidence that OT with the use of therapeutic grade essential oils had a direct, positive impact in recovering total loss of smell in just a few short days.
About the Author: Lisa resides in Indiana with her husband and three children. Due to the pandemic, they decided to homeschool this year, which has been such a blessing! She recently received her French Aromatherapy Certification, holds both a B.S. in Education and an M.S. in Communication Sciences and Disorders. Lisa discovered essential oils nine years ago, was intrigued by the diversity of using oils for therapeutic use, began to dive further into inquiry, which then led her to pursue certification. Besides assisting others with holistic wellness goals, Lisa is a Speech-Language Pathologist working with children with speech/language disorders.
Aromatika Magazine: This article was originally published in Aromatika, a quarterly e-journal focused on aromatherapy, herbal medicine, and complementary therapies targeting professionals working in complementary and alternative medicines. Learn more here.
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