What is an Essential Oil?

Essential oils are leading natural solutions for a variety of ailments because of their potency and proven properties and benefits. With their increasing popularity among the general public and health professionals, more people are seeking factual information that can help them use them safely and effectively. So, what are essential oils? It turns out defining what an essential oil is is much harder than you think.

Traditionally, the aromatherapy industry has held to the following definition, likley adopted from an earlier definition used by the flavor and fragrance industry:

The National Association for Holistic Aromatherapy (NAHA) defines essential oils as highly aromatic substances made in plants extracted by distillation. [1] They further explain that essential oils can be extracted by steam distillation, hydrodistillation (also called water distillation), or expression. [2] The NAHA prefers to call substances extracted by enfleurage, solvents, and carbon dioxide (CO2) as extracts rather than essential oils. Interestingly, the NAHA alludes to accepting CO2 extracts as essential oils when they state “An essential oil’s chemical make-up may vary from the plant from which it was extracted from due to its method of extraction; for example, distillation vs. carbon dioxide extraction vs. expression.”

Another industry organization, the Alliance of International Aromatherapists (AIA) does not have an official definition that I could find on their website. [3]

However, some scientists and scientific organizations allow for a broader definition:

“An essential oil is a product made by distillation with either water or steam or by mechanical processing of citrus rinds or by dry distillation of natural materials. Following the distillation, the essential oil is physically separated from the water phase.” is a definition that closely matches that given by the NAHA for an essential oil by the International Organization for Standardization (ISO). [4]

A 2012 review article published in The Journal of Essential Oil Research states that essential oils can be obtained from plants by “hydrodistillation, solvent extraction, cold pressing, and supercritical fluid extraction (CO2).” [5] The article also notes that essential oils are most commonly extracted by steam distillation.

Similarly, a 2018 review article from the Asian Journal of Green Chemistry includes a variety of extraction methods for essential oils, including steam distillation, hydrodistillation, solvent extraction, supercritical fluid extraction, instantaneous controlled pressure drop process, microwave-assisted extraction, and ultrasound assisted extraction. [6] The article further states that the traditional methods of extraction (steam distillation and hydrodistillation) have several drawbacks, which led to the emergence of newer processes to “optimize the performance of the essential oil in both quantitative and qualitative terms.”

Another review article from 2015, uses a simple definition that essential oils are “a mixture of saturated and unsaturated hydrocarbons, alcohol, aldehydes, esters, ethers, ketones, oxides phenols and terpenes, which may produce characteristic odors” and “extracted from the flowers, barks, stem, leaves, roots, fruits and other parts of the plant by various methods.” [7]

A study even specifically calls a CO2 extract a “supercritical essential oil.” [8]

While another study considers CO2 extraction as an innovative technique to extract essential oils allowing for the extraction of additional essential oils that cannot be obtained with traditional methods. [9]

A recent symposium (Essential Oil Symposium for Medical Professionals) I attended that included some of the foremost and respected researchers and clinicians on essential oils defined essential oils as “distilled or extracted from a single botanical variety [where] nothing is added or taken away.” This means no addition of natural isolates, synthetic petrochemicals, or cheaper essential oils. Supercritical CO2 extracts can certainly meet this definition because they do not add any residual solvent.

Even Josh Axe, DNM, CNS, DC weighed in on the subject during an interview with Shape Magazine, defining essential oils as “highly concentrated compounds extracted from plant parts using a steam-distillation, cold pressing, or CO2 extraction process.”

I could cite dozens, maybe hundreds, of additional studies that accept aromatics extracted by CO2 as essential oils. [10],[11],[12],[13]

Why must we hold to such a limited definition of essential oils—oils obtained only by distillation or expression—when CO2 “select” extraction can produce an end-product very similar to—sometimes even superior to—traditionally distilled essential oils without leaving residual solvent? For example, CO2 bergamot can produce an oil similar to expressed bergamot, distilled caraway closely resembles CO2 caraway, CO2 lemon and expressed oils composition are comparable, CO2 tea tree produces an oil similar to distilled oil but with less loss of bioactive constituents due to thermal degradation, and many more essential oils could be cited.

Indeed, I recently asked a group of trained aromatherapists to review the complete composition of 10 essential oils and tell me whether it was a distilled or expressed essential oil or one extracted by CO2. Trained aromatherapists were only able to correctly identify the extraction method about 50% of the time, which is not statistically different than guessing really. This emphasizes that many CO2 oils look just like traditionally extracted essential oils when you compare compositions.

In addition, some essential oils extracted by CO2 may be more therapeutic due to the preservation of bioactives. For example, supercritical German chamomile select CT bisabolol oxide essential oil contains similar levels of bisabolol oxide A (50.4% to 56.8%), bisabolol oxide B (0.2$ to 21.5%), alpha-bisabolol (1.5% to 8.9%), and sometimes minor amounts of chamazulene (0.0% to 1.8%)—some of the key active constituents in the oil identified by research—while preserving some matricine (up to 3.5%). This is highly desirable because matricine is significantly more anti-inflammatory than chamazulene.

Another example is supercritical ginger select essential oil. Gingerols and shogaols are pungent compounds found in ginger roots with proven anticancer, antiobesity, antiallergic, antioxidant, and anti-inflammatory properties. These compounds are not present in distilled ginger essential oil but the selectivity and better extraction properties of CO2 allow these health-promoting constituents to appear in high levels in CO2 ginger essential oil while still maintaining other key bioactives (e.g. alpha-zingiberene, beta-sesquiphellandrene).

Instead, I propose that we accept as essential oils any plant extract that produces an end-product similar to traditionally distilled essential oils without introducing a foreign substance (such as animal fat or solvents) during the extraction process. This would allow select CO2 oils, distilled oils, and expressed oils to each be called essential oils being delineated as such: supercritical lemon essential oil (select), distilled lemon essential oil, and expressed lemon essential oil. Absolutes would not be included as an essential oil because they leave trace to small amounts of solvent in the end-product.

One argument against using CO2 essential oils in clinical practice has been the lack of safety information because of the presence of these additional constituents. However, I performed a literature review on the safety of these constituents and list additional cautions in my book “SuperCritical Essential Oils” based on these new constituents. For the clinician, the name and definition are not as important as reliable efficacy and safety. Supercritical essential oils may produce more therapeutic end compositions making them a great addition to the clinician’s natural toolbox.

Essential oils could therefore be defined as “mixtures of volatile aromatic compounds and select nonvolatile compounds (e.g. coumarins and fatty acids) extracted from plants by various methods that do not introduce foreign substances (e.g. solvent residue) during the extraction process.” Doing so, allows us to use plant extracts for therapeutic purposes to improve overall well-being and removes self-imposed limitations.

A consensus definition among scientists, health professionals, and the aromatherapy community will likely never be obtained. More importantly than a consensus definition, scientists and sellers of essential oils should clearly delineate what extraction method was used for the product they are evaluating or selling. So the bottom line is, the definition of essential oils depends on whether you abide by traditionally held views, definitions from published research, or a hybrid.

The Berlin Wall of Aromatherapy Must Fall for Advancement and Healing

Constructed beginning in 1961, The Berlin Wall was built to divide East and West Germany physically and ideologically following the conclusion of World War II. This wall was erected to protect against the principles of freedom and democracy seen as the enemy by Soviet-controlled Germany. It was a physical and mental way to maintain control. Similarly, proverbial walls are erected in the aromatherapy community to protect against what some see as the enemy to the status quo.

There is an entrenched group among traditional aromatherapists who see it as their mission to protect aromatherapy from “outsiders” no matter the consequences. They seek shelter from health professionals and researchers that have a passion for essential oils, from individuals and companies that market essential oils in a network marketing model, and most of all ideology that comes from an unfamiliar perspective and falls outside established paradigms.

Until recently, I felt like people on both sides of the Berlin Wall did in the 1970s—that the demise of the walls of aromatherapy would never occur. That all changed when I met a 40 plus year veteran and traditional aromatherapists, Sylla Sheppard-Hanger. Rather than reject me outright, we had multiple communications to seek a better understanding of one another. She epitomized the old adage “seek first to understand and then to be understood.” Our conversations gave me hope and for the first time in my professional career, I felt respected by a long-time leader of the traditional aromatherapy community.

Unfortunately, this hope was immediately diminished by the sharp criticism I have come to know well and expect from the traditional aromatherapy community. Sensing the walls of aromatherapy were weakening, a group of traditional aromatherapists vehemently rejected the efforts of Sylla to unify aromatherapy and dug in their heels to maintain the existing state of affairs.

One proclaimed on Facebook “Really? Not a fan of Scott Johnson. These type of books [referring to my essential oil reference books] should be written by aromatherapists and other professionals who work in this field.” This statement is akin to the segregation practiced in the 18th and 19th centuries in America and is wholly inaccurate—I have a certificate in aromatherapy from an aromatherapy school. It is a judge the book by its cover mentality without even evaluating the information it contains. It is willful ignorance at its best. Indeed, no other person has added more evidence-based pages to aromatherapy and essential oils than I have in the last decade. Contributions that have largely been ignored or disrespected.

I have witnessed similar attacks against chiropractors and other health professionals who have made valuable contributions to aromatherapy. The reality is that these health professionals not only look at essential oils from a fresh perspective that can lead to innovations, but they are also likely more qualified to discuss clinical aromatherapy because of their greater knowledge of biology, anatomy, physiology, molecular mechanisms, cellular function, organ system function, and so forth.

The overwhelming majority of published papers on essential oils are written by scientists that are not aromatherapists. Does this mean we should reject their works too because they don’t abide by the unwritten rule that only writings from aromatherapists are valid? Indeed, it wasn’t a traditional aromatherapist that the medical community sought out when a chapter on essential oils was needed for a medical textbook. Instead, they chose me and my colleague to write the chapter because they recognized our evidence-based approach.

Another deep-rooted dogma among traditional aromatherapists is the belief that network marketing is ruining aromatherapy. Whether methods of use or sales model in general, many traditional aromatherapists abhor network marketing companies involved in aromatherapy.

In truth, network marketing companies have done more to advance the popularity and acceptance of essential oils—in both the general public and medical/scientific community—in the last decade than any other factor. They also tend to invest money into research that advances our scientific knowledge of essential oils and make sizeable donations to hospitals and medical centers that advances the use of essential oils in clinical settings.

Methodological differences exist, but network marketing companies aren’t too far from moderate methodology taught in aromatherapy. I have been called a “quack” and one who promotes “dangerous” practices because I take a moderate approach to essential oils. The biggest reason for this is my stance on oral administration and neat topical application. There is sufficient evidence (through published research and millions of user experiences) now to confidently say that ingestion of most essential oils is safe and an effective way to experience benefits. So much so, that insisting that you cannot ingest essential oils is not only obsolete it is anti-science.

When it comes to topical application, my books provide ranges of dilution, some of which allow for the neat application of essential oils. What people overlook is that I teach dilution is a more effective way to use essential oils because it improves absorption. I teach that dilution should be practiced in most cases and neat application reserved for a few instances such as toenail fungus, trace amounts on a bug bite, or application to a mouth sore. Most of the time, dilution up to 50% (depending on the oil being used and the purpose) is the best option for both safety and efficacy. Moreover, I was among the first—if not the first—to report that people with compromised immune systems are more prone to skin irritation by essential oils.

Sylla agrees that oral use and topical application I higher dilution above normal guidelines (up to 50%) is warranted, “I have learned in 40 years of practice on myself and others that sometimes higher dilution above normal (up to 50%) or internal use is called for.” She continues on the topic of safety, “Once we have the proper information and safety data we can make safe and effective remedies. There is no need to be scared to use our oils, just be scared enough to know your oils safety and use appropriately.” In other words, become properly educated on the composition, usage guidelines, and cautions of essential oils through an evidence-based book or aromatherapy certification to use them more confidently.

Other traditional aromatherapists consciously reject the truth—despite the preponderance of evidence—to pander to their prejudices. They argue until they are blue in the face, using much speaking to support their established beliefs even when inaccurate. For them, it is easier (or maybe an ego thing) to maintain paradigms than change (or maybe admit they were wrong).

Instead of building walls, I encourage both sides to build bridges. Let’s focus on our common love and passion for essential oils and other natural solutions. Together, we can work on more pressing issues than arguing with one another, like essential oil quality and adulteration, sustainability, maintaining medical freedom, and increasing the use of essential oils in mainstream clinical settings.

Sylla makes an impassioned plea to her colleagues, “For the good of the global aromatherapy community and the health of the world, it is time for us to come together, and learn what we can from each other instead of ‘othering.’  Let’s move forward together, it feels so much better and creates bridges instead of walls.”

Just like the Berlin wall fell in 1989 due to a series of revolutions by brave reformist-minded individuals, the walls of aromatherapy need to come tumbling down for healing and the advancement of essential oils. The demise of the aromatherapy walls, built over decades, will lead to improved collaboration and the advancement of aromatherapy and essential oils. As Ronald Reagan stated, “tear down this wall.” Make a commitment today to reach across the aisle and seek commonality and to understand one another. We will all be better for it.

The Keto Diet: Fad or Fabulous?

All diets are fads. Short-term means to an end rather than a healthy way of eating. Nevertheless, some diets are repeatedly resurrected and repackaged. Such is the case with the low-carb high-fat diet, of which the most recent cult craze is the ketogenic diet—keto for short.

What is the keto diet?

Originally developed to treat severe epilepsy in infants and children, the keto diet is a low-carb, high-fat diet that is largely adopted today to lose weight. Clinical keto diets limit carbs to 20 to 50 grams per day (primarily from nonstarchy vegetables). Protein is kept at a minimum to maintain muscle mass without disrupting ketosis—amino acids (glutamine and alanine) can be converted to glucose through a process called gluconeogenesis, which could move the body out of ketosis. [1],[2] But even this is controversial and scientists are still evaluating the long-term effects on muscle mass caused by the keto diet. The keto diet shares many similarities with the Atkins diet and other low-carb diets.

The keto diet simulates a fasted state and after three to five days of following a very low-carb diet your body is deprived of sugars and starches it was used to relying on for fuel. This causes a reduced secretion of insulin and forces the body to burn fat for fuel instead. The result is an overproduction of acetyl-CoA that places the body in a state called ketosis (or ketogenesis)—a state in which a type of acid called ketones (beta-hydroxybutyric acid and acetone) are the primary fuel for your body. Glucose (blood sugar) is the preferred fuel source for many cells in the body and when it is limited, the body uses fat as a fuel source.

Brain function is strongly linked to glucose levels and how efficiently the brain uses it as a fuel source. However, in a state of ketosis, the glucose-hungry brain uses ketones—that can cross the blood-brain barrier—for fuel. In the end, your body’s organs, tissues, and cells make dramatic adjustments to their new energy source.

Several variations of the keto diet exist:

  • Standard—Very low-carb (5%), moderate protein (5–20%), high-fat (75%–90%)
  • High-protein—Very low-carb (5%), high-protein (35%), high-fat (60%)
  • Cyclical—Alternating periods of high-carb days with ketogenic days
  • Targeted—Consuming carbs during or near exercise

Benefits of the keto diet

Most people use the keto diet to rapidly lose weight. Any diet that removes or severely limits carbs usually causes rapid weight loss due to a corresponding caloric restriction. In addition, the keto diet can produce a more steady delivery of energy to organs and tissues, which reduces cravings and hunger. [3] Studies show that the keto diet does promote weight loss, some of which reported that it is more effective than a low-fat diet, but the highest quality studies show them equally effective. [4] Most people will experience initial rapid weight loss on the keto diet.

As stated above, the keto diet was originally developed for children with hard to control seizure disorders. The diet helps control epilepsy through multiple mechanisms and biochemical alterations that reduce excess neuron excitability. [5] Doctors and scientists state that efficacy requires at least three months of a ketosis state. One major drawback to using keto for epilepsy is most people discontinue the diet because of its restrictions and diminished palatability.

Diabetes is characterized by metabolic changes such as high blood sugar and impaired insulin sensitivity. The keto diet promotes the release of excess fat, which can reduce the risk, or burden, of diabetes alone. Research also suggests that the keto diet may improve insulin sensitivity and reduce diabetic medication requirements. [5],[6]

Ketones, especially beta-hydroxybutyric acid, protect brain cells against damage caused by multiple types of assaults and emerging research suggests it may be beneficial for neurodegenerative disorders like Alzheimer’s disease and Parkinson’s disease. [7] Although the mechanisms of neuroprotection are not fully understood, these benefits may be due to improved brain cell signaling, restoration of neurotransmitter channel functions, improved cellular energy, and maintenance of cellular homeostasis. [8] The keto diet may also improve cognition and reduce age-related cognitive decline. [9]

Preliminary evidence also suggests that the keto diet has anti-cancer effects. [10] However, more study and research is necessary to determine if the keto diet has a place as an adjunct to cancer treatment.

What are the risks and dangers?

One of the primary risks of the keto diet is an increased risk of cardiovascular disease. A high-fat diet can lead to elevated triglycerides, increased atherosclerotic plaque, and harmful metabolic changes that increase the risk of cardiovascular disease. [11],[12],[13] This is ironic since many obese individuals use the keto diet to lose weight to reduce the risk of obesity-related cardiovascular problems.

Very low carb intake has been linked to premature death. [14] In fact, the researchers concluded that both low-carb and high-carb diets are associated with an increased risk of early mortality. The sweet spot seemed to be about 50%–55% carbohydrate intake that emphasizes plant-based foods—fat and protein from sources such as vegetables, nuts, whole-grains, and peanut butter—to promote longevity.

In order to force the liver to pump out ketones, the keto diet severely limits carbs, dramatically reducing the intake of the most nutritious foods—fruits and vegetables. These foods are a good source of dietary fiber, which maintains bowel health, helps control blood sugar, promotes a healthy weight, and lowers cholesterol levels. In addition, diets with insufficient fiber are associated with gastrointestinal disorders and colorectal cancer. [15],[16],[17] Constipation is a common adverse effect of the keto diet.

While neuroprotective benefits have been observed when adhering to the keto diet, high-fat diets also promote deterioration in memory, attention, processing speed, and mood, and increases brain inflammation. [18],[19] This suggests that high fat intake may negate or even reverse the cognitive benefits of ketones.

Increased risk of kidney stones is a well-known consequence of the keto diet, occurring in about 1 in 20 children. [20] To reduce this risk, individuals should ask their healthcare provider about supplementing with potassium citrate. The keto diet can also be dangerous for people with kidney disease. People with kidney disease often need to consume a low-protein diet, which may not align with the keto approach.

Reduced insulin levels caused by the keto diet cause your kidneys to release more electrolytes. [21] This can lead to dehydration and the “keto flu”—flu-like symptoms, constipation, cramps, irritability, and other symptoms lasting form a few days to weeks.

It goes without saying that if you reduce fruit and vegetable intake you are at a greater risk of nutrient deficiency. [22] These foods are loaded with vitamins, minerals, and other beneficial phytonutrients that maintain optimum function of your mind and body.

Bonus: Naturally increase ketones without resorting to the keto diet

It is well-known that prolonged fasting and the keto diet raise ketone levels. But, what if there was a natural way to boost ketones without the risks of the keto diet? This may be possible by leveraging a compound found in mangos—mangiferin. Mangiferin stimulates the liver to produce ketones leading to significantly increased blood levels of ketones according to clinical research. [23] The study participants consumed 150 mg of mangiferin per day for 12 weeks, which increased beta-hydroxybutyrate by about 18% and acetoacetate by about 10%. Mangiferin supplementation also increased insulin sensitivity. This study suggests a safer way to increase ketones without resorting to a restrictive diet.

Conclusion

While weight loss and other benefits are possible with the keto diet, it is not a sustainable or long-term way to eat. The potential problems of the diet outweigh the benefits in the long-term. The keto diet is best reserved for people who have a specific medical condition for which it is indicated or who plan to use it for a short period to kick start weight loss (even this must be carefully considered). Ultimately, the high fat content—especially saturated fat, limited nutrient-rich fruits and vegetables, and health risks of the keto diet make it a concern for long-term health.

Alternatives to the flu shot frenzy

Pharmacies, health practitioners, grocery stores, and big-box stores all heavily push the flu vaccine this time of year. It’s hard to go anywhere without being bombarded by advertising for the annual flu shot. This frenzy occurs to capture a piece of the flu shot money pie. There is big money to be made for both the manufacturers and those administering the vaccine. But, given the questionable ingredients and lackluster effectiveness of the vaccine, many people are seeking alternatives to the flu shot.

What is the flu?

Influenza, or the flu for short, is a contagious respiratory system infection caused by a group of viruses known as influenza. Human influenza viruses A and B are the strains responsible for the flu experienced in humans during the winter months. It spreads from person to person by contact with tiny droplets expelled into the air when infected people cough, sneeze, and even talk. Contaminated surfaces are less often the cause of transmission from one person to another.

What are the symptoms of the flu?

The flu can cause mild to severe illness depending on the age and health of the person. Its hallmark symptoms include:

  • Fever
  • Chills
  • Headache
  • Body aches
  • Cough
  • Sore throat
  • Runny or stuffy nose

Flu shot efficacy

According to the U.S. Centers for Disease Control and Prevention, the 2018–2019 flu shot had an adjusted vaccine efficacy of just 29% for all ages. People at greatest risk of the flu—elderly individuals aged 50 and older and infants 9 to 17 months—fared worse with vaccine efficacy of only 12% and 6% respectively. Between 3% and 11% of people get the flu each year, making the 6% to 12% figures hardly significant and causing one to question whether you are receiving any protection at all by getting the flu shot each year.

Harmful and questionable ingredients in the vaccine

In addition to poor efficacy, some choose not to have the flu shot because of the harmful and questionable ingredients they contain. Chief among these is mercury (thimerosal), which is added to prevent the growth of microbes. Research links thimerosal to neurological damage, especially in children, by interfering with folate-dependent methylation. Moreover, the vaccine also contains toxic formaldehyde, aluminum, chicken egg proteins, gelatin, polysorbate 80, and antibiotics that have various risks.

Natural flu shot alternatives

Vitamin D. One of the most important steps to support healthy immune function is to take therapeutic levels of vitamin D when the flu virus is most virulent. In fact, some experts hypothesize that flu season is directly correlated to a lack of vitamin D synthesis in the skin because humans are not exposed to sufficient sun during less sunny months. Indeed, research suggests that supplementing with vitamin D—a very inexpensive supplement—can reduce the risk of flu with better efficacy than the bleak 29% of last year’s flu shot. Elementary-aged children should take 2,000 IU of vitamin D daily, while teens and adults should take 2,000 to 5,000 IU daily for optimal protection.

Probiotics. Given that up to 70% of your immune system lies within your gut, it is no surprise that taking a probiotic can reduce your risk of flu. One study found that taking combinations of various probiotic strains—three to five strains including Lactobacillus plantarum LP01 or LP02, Lactobacillus rhamnosus LR04 or LR05, and Bifidobacterium lactis BS01, lactoferrin, and prebiotics—reduced flu-like respiratory illnesses by a remarkable 75%. The probiotics also reduced symptom severity in people who did get the flu, by a significant 37%. Take a probiotic at least once daily with at least three of the above mentioned numbered strains.

Elderberry. Clinical research confirms that elderberry syrup (15 mL, four times daily) reduces the length and severity of flu symptoms, but it can also be taken to maintain healthy immune function. Most manufacturers recommend one teaspoon (5 mL) daily to maintain healthy immune function.

Essential Oils. As shown in Medicinal Essential Oils, some essential oils contain anti-viral properties and some demonstrate specific activity against the flu. These include tea tree, cinnamon bark (its primary constituent cinnamaldehyde), orange, clove, eucalyptus, rosemary, and melissa. Blending these oils together and taking two to three drops of the blend in a capsule, twice daily, may help support healthy immune function.

The evidence-based conclusion

Rather than expose your body to a largely ineffective and potentially harmful flu shot, keep your immune system in tip-top shape with natural products. Taking more than one of the solutions above is likely to enhance the protective effects you experience. By doing so, you’ll stay healthy during the challenging winter season and avoid missing life’s important celebrations.