Protected: Can you decipher the difference between essential oils extracted by CO2 (supercritical) and traditional (distilled/expressed) methods?

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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.

Eating dark chocolate may improve mood

Mood disorders affect almost ten percent of U.S. adults and nearly fifteen percent of adolescents, according to the National Institute of Mental Health. With so many people suffering from mood disorders people are looking for answers in nature and food. Fortunately, a recent study suggests eating a common treat—dark chocolate—may positively affect mood and relieve depressive symptoms.

Researchers from University College London joined forces with Canadian scientists from the University of Calgary and Alberta Health Services Canada to assess the benefits of chocolate consumption on mood. They analyzed data from over 13,000 adults included in the US National Health and Nutrition Examination Survey and assessed their depressive symptoms according to scores on the Patient Health Questionnaire. Other factors such as height, weight, marital status, ethnicity, education, household income, physical activity, smoking, and chronic health problems were taken into account to ensure the study only measured the effects of eating chocolate on mood.

Remarkably, what the scientists found was that people who reported eating dark chocolate in two 24-hour periods had 70% lower risk of reporting relevant depressive symptoms, even after adjusting for the above-mentioned confounding factors. (1) In addition, people who were in the top 25% of eating any type of chocolate were the least likely to report depressive symptoms. The study suggests that eating a bit of dark chocolate on a regular basis can positively benefit mood.

Chocolate contains several beneficial nutrients—fiber, iron, magnesium, copper, manganese, selenium, and zinc—and phytocompounds—powerful antioxidants and flavanols—that have proven health benefits. (2) For example, chocolate flavanols improve vascular function and reduce blood pressure. (3a, 3b, 3c) The antioxidants protect cholesterol against oxidation, which can reduce heart disease risk. (4) Interestingly, improved blood flow triggered by chocolate flavanols may also protect the skin against sun damage by increasing blood flow increasing hydration and density. (5) Eating flavanol-rich cocoa can even improve brain function. (6)

Among these beneficial ingredients are phytocannabinoids that can produce a feeling of euphoria when consumed. (7) Phytocannabinoids have the ability to bind to receptors in the endocannabinoid system, which regulates mood stress, response, immunity, inflammation, and much more. This stimulates an endorphin release that has an antidepressant-like effect and elevates mood.

Food is a significant and easy way to alter mood levels because of the effects of food consumption on dopamine receptors in the brain. Certain food ingredients (like chocolate) interact with these receptors to activate the reward and pleasure centers of the brain. Scientists have even observed that people may crave foods that contain these pleasure-triggering ingredients when feeling sad.

Dark chocolate contains 50%–90% cacao solids, whereas milk chocolate contains from 10%–50% cacao and significantly more sugar. A reasonable portion of dark chocolate to reap health benefits is about 10 to 40 grams per day. Some studies report benefits with as low as 6.3 grams consumed, while others found benefits at 48 grams. However, keep in mind that 40 grams of dark chocolate can provide 220 calories and 13 grams of fat, so don’t overdo it at the expense of your waistline.

So go ahead and indulge in a little dark chocolate to help improve your mood and promote greater happiness. It’s certainly an easy way to stimulate the production of endorphins, create feelings of pleasure, and promote a positive mindset.

Q&A: Does Applying Essential Oils to the Belly Button Lead to Systemic Delivery?

The umbilical cord—consisting of one large vein and two smaller arteries—forms very early in pregnancy and serves to shuttle oxygenated blood from the mother to the baby and deoxygenated blood and waste from the baby to the mother. The umbilical vein carries oxygenated blood from the placenta to the fetus, and the umbilical arteries carry deoxygenated, nutrient-depleted blood from the fetus to the placenta. Shortly after birth, the umbilical cord is clamped and cut leaving us with a constant reminder of the nourishment we received from our mother in the form of a belly button (also called the umbilicus or navel).

Once cut, the exterior remnant of the umbilical cord withers away and turns into a firm stump until it falls off. But what about the blood vessels that once exchanged blood between mother and baby behind the belly button? The part of the blood vessels closest to the belly button degenerates into a ligament called the round ligament. This ligament extends from the belly button to the porta hepatis—a deep fissure on the surface of the liver where neurovascular structures (except the hepatic veins) and hepatic ducts enter and leave the liver—where it joins with the ligament vernosum (the fibrous remnant of fetal circulation) to separate the left and the right lobes of the liver. The round ligament contains some small veins, called paraumbilical veins, which can expand when high pressure occurs in the veins around the abdominal organs.


Two additional ligaments are formed from the remnants of the umbilical cord behind the belly button. The medial umbilical ligament runs from the belly button to the liver and contains the obliterated arteries of the umbilical cord, whereas the median umbilical ligament is formed from the veins. Essentially, the inside of the umbilical cord behind the belly button degenerates into connective tissue and becomes a vestigial remnant.

Recently, essential oil users have adopted a technique used by cannabis users called the Pechoti method and administered essential oils through the belly button. This method is commonly used among cannabis users to absorb CBD and THC into systemic circulation. The claim is there is a gland called the Pechoti gland behind the belly button that houses more than 72,000 veins and millions of nerves. When substances are applied in or on the belly button, this gland distributes the substances into systemic circulation. However, the existence of the Pechoti gland is not accepted in science and there isn’t any actual evidence to suggest this gland is present.

Essential oils rely on entrance into systemic circulation through capillaries (the smallest blood vessels in the body that are only one endothelial cell thick) not veins. Since the belly button does not have a noteworthy capillary supply, it is not likely that essential oils will enter systemic circulation via this route. Instead, you are more likely to experience a localized effect to the abdominal region. There are however some capillaries within the abdominal region, so it is possible small amounts of essential oil may enter systemic circulation.

A more practical approach for systemic circulation is to take the essential oils in a capsule or sublingually. This method will result in more essential oil reaching systemic circulation. So, for now, this method seems to be more myth than reality.

The powerful influence of smell on memory, emotions, and overall health

Although one of the least explored senses in the field of research, the sense of smell (or olfaction) may be one of the most important senses for overall health. Smell has a unique relationship with memory and emotions that is unmatched. No doubt you’ve experienced déjà vu due to exposure to a scent. This familiar and memorable aroma—like grandma’s oatmeal chocolate chip cookies, your dad’s garage, new car smell, or the flowers outside the house you grew up in—activates specific areas of your brain reigniting vivid memories and emotions. These nostalgic experiences intimately linked to aromas are called scent memories and demonstrate just how powerful the sense of smell is.

Your sense of smell is directly connected to your brain. Functional magnetic resonance imaging shows that when you smell something two parts of the brain are activated—the amygdala and hippocampus. The amygdala is the emotional center of the brain and the hippocampus plays a major role in memory, so it is not surprising that scents arouse powerful memories and emotions. Indeed, a captivating and familiar aroma has the power to not only remind you of a past person, place, or event, but it triggers emotions more powerful than those generated by other senses like sight and sound. (1)

Collectively, the amygdala and hippocampus (both parts of your limbic system) coordinate a conditioned response that rapidly links familiar aromas with their associated memories. Other senses (visual, auditory, and tactile) do not pass through these areas of the brain, which explains why aromas produce greater emotional responses than the other senses.

Scientists are just beginning to understand the complexity of the sense of smell and its involvement in human health. The discovery of olfactory receptors outside the nasal cavity in areas such as the kidneys, heart, skin, and immune cells highlighted a wider role for olfaction in human health than previously known. (2) A growing body of evidence suggests that olfactory receptors not only play a role in the function of multiple organs and systems, but they also have potential to be used in the prevention, diagnosis, and treatment of disease. (3) This research has revealed that olfactory receptors perform important functions such as:

  • Regulate heart function.
  • Promote death and reduce the spread of certain types of cancer cells.
  • Regenerate skin cells to speed the wound healing process.
  • Promote prostate health.
  • Aid digestion.
  • Regulate blood pressure.
  • Stimulate insulin secretion by the pancreas. (4)
  • Regulate appetite. (5)

Nostalgic memories and positive emotions can also be produced by the potent aromatic molecules found within essential oils. When an essential oil is smelled, aromatic molecules are carried by olfactory sensory neurons to the olfactory bulb. The olfactory bulb filters and processes the incoming signals and then mitral cells carry an outgoing signal to the olfactory cortex and the limbic system, which includes the amygdala and the hippocampus. A wide variety of psychophysiological responses occur in response to this outgoing signal that can promote improved health. Here are a few essential oils associated with improved memory and emotions:

  • Citrus oils like lemon, orange, and tangerine are strongly uplifting. Inhalation of citrus fragrance helped normalize neuroendocrine hormone levels and immune function in people diagnosed with depression and was deemed more effective than antidepressants. (6)
  • Rosemary is called the herb of remembrance and for good reason. Teen boys and girls (aged 13 to 15 years old) experienced significantly improved short-term memory when they inhaled rosemary essential oil. (7)
  • Lavender essential oil is associated with a more relaxed state. Healthy individuals who inhaled lavender essential oil reported feeling fresher and more relaxed than individuals who inhaled a base oil. (8)

These few studies—and many more existing studies—show that essential oils can improve mood and memory function simply through inhalation. For more research to support the use of essential oils for memory and emotions, see Medicinal Essential Oils: The Science and Practice of Evidence-based Essential Oil Therapy.

The power of the sense of smell should not be overlooked nor underestimated. The evidence is clear that olfaction plays a significant role in overall human health, so don’t cut your health short. Stop to smell the roses and be sure to incorporate essential oil inhalation into your regular daily routine.

The Real Risk of Lavender and Other Essential Oils for the Hormone System

A recent study reignited fear and confusion in parents about one of the most versatile and trusted essential oils—lavender—and whether it has estrogenic properties. The study published in the Journal of Clinical Endocrinology & Metabolism claims an association between lavender products and premature thelarche (PT; the development of small breasts typically before age three) and prepubertal gynecomastia (PG; the growth of breast tissue in males).

Dozens of sensationalized articles ran with this study’s assertions blurring the line between good scientific journalism and clickbait publicity. Most journalists only read the study abstract and do not dive deeper into the methodology and other important details, which leads to an oversimplification and sometimes misinterpretation of the results. Many health professionals and well-meaning people spammed their family and friends with these oversimplified and misconstrued articles to “prove” they should not use essential oils. So, is it time to throw out lavender and tea tree essential oils and avoid their use in children, or is this a case of scientists untrained in and ignorant of essential oils making absurd conclusions?

Previous research findings

Previously, a study argued that chronic lavender exposure caused PG, while another study alleged that both tea tree and lavender “probably caused” PG in boys. These studies spread like wildfire because they create doubt in people’s minds whether they should use one of the most popular and effective natural solutions available—essential oils. However, one should be cautious in jumping to conclusions and remember correlation does not mean causation.

The first study contains three case reports of PG that resolved after the discontinuance of lavender-containing products. One was a shampoo with lavender listed as an ingredient and the other two regularly used the cologne agua de violetas. They analyzed the cologne with HPLC, and based upon an “assumption” and comparison with an analysis of lavender essential oil concluded that linalool and linalyl acetate were components of the cologne.

The scientists failed to provide the full HPLC analysis of the oil for verification of lavender biomarkers and to rule out synthetic and adulterant markers. Given the substantial adulteration of lavender essential oil and the common practice of perfumers to use petroleum-derived synthetic chemicals (like synthetic linalyl acetate), it is highly likely that the cologne does not contain true lavender essential oil but synthetic bioidentical chemicals. It is also probable that an adulterated lavender was used in the shampoo product. In addition, reports show that about half of tea tree oil samples don’t meet the composition standards to be considered genuine and pure tea tree oil.

If you want to read the flawed science of the latter study, I invite you to review page 24 of my book Medicinal Essential Oils. For additional insight into how these studies are flawed—including confounding false-positive results due to the use of 96-well plates and the fact that essential oils may extract plastic chemicals up to 10,000-fold—see my Facebook live video.

Estrogenic activity of lavender and tea tree essential oils

Each of these studies validity is entirely dependent on lavender (or tea tree) producing sufficient estrogenic effects to disrupt the endocrine system. However, compelling evidence suggests lavender and tea tree do not have estrogenic potential.

The rat uterotrophic assay is the gold-standard test in living organisms to detect the estrogenic activity of a substance. During this test, immature female rats are repeatedly exposed to doses of a substance for three days. The weight of their uterus is measured on the fourth day, which provides a sensitive and toxicologically relevant measurement of the estrogenic activity of the tested substance.

In 2013, scientists evaluated the estrogenic effects of topical lavender in the rat uterotrophic assay. Immature female rats were administered 20 or 100 mg/kg of body weight over (roughly the equivalent of an adult applying 1.5 mL to 7.5 mL of lavender essential oil each day for three days) the course of three days. A positive control group was administered 2.5 mcg/kg of 17α-ethinyl estradiol (a synthetic estrogen used in birth control pills). The weight of the uterus and ovaries were recorded 24 hours after the final dose was administered. As expected, the positive control group that received 17α-ethinyl estradiol experienced significant increases in mean absolute and relative uterine weights. However, uterus weights of the lavender treated group did not increase relative to normal values. The scientists concluded that lavender essential oil “was not active in the rat uterotrophic assay and gave no evidence of estrogenic activity.”

Tea tree has not been tested in the uterotrophic assay, nor could any convincing research be found supporting an estrogenic or hormone-disrupting effect. Although a group of scientists contended that individual chemicals within tea tree oil disrupt hormone function, they relied upon flawed methodology that in essence makes their finding invalid (see the Facebook video above for more details).

The most recent study again used an in vitro (laboratory) method by placing human cells in 6-well, 24-well, and 48-well plates. While the authors took measures—also assessed soybean oil—to assess whether essential oils dissolved plastic chemicals in the plates to elicit the observed hormonal activity, they did not use the gold standard in vivo (performed or taking place in a living organism) rat uterotrophic assay. In vitro studies don’t always correlate with in vivo studies, and particularly human clinical studies. With the conflicting results in these studies, the appropriate approach is to weigh the in vivo study results more heavily. In other words, the in vivo study that suggests lavender has no estrogenic activity supplants the most recent study that reported lavender has estrogenic activity in laboratory research.

Lavender and tea tree essential oil major constituents

Essential oils are complex mixtures of volatile aromatic molecules. They can contain from a dozen to hundreds of constituents depending on the oil. The ratio of these molecules is what gives essential oils their therapeutic benefits. It is also known that certain essential oil constituents can synergize, buffer, or counteract the effects of another constituent in the oil.

To aid in this discussion the typical percentages of major constituents in lavender and tea tree essential oil are provided.

Lavender

  • Linalyl Acetate 25%–45%
  • Linalool 25%–45%
  • (Z)-Beta-Ocimene 2%–8%
  • Beta-Caryophyllene 2%–6%
  • Lavandulyl Acetate 2%–6%
  • Terpinen-4-ol 1%–6%

Tea Tree Oil

  • Terpinen-4-ol 35%–48%
  • Gamma-Terpinene 10%–28%
  • Alpha-Terpinene 5%–13%
  • Alpha-Terpineol 2%–8%
  • Alpha-Pinene 1%–6%
  • Terpinolene 1%–5%

Penetration enhancing effects of essential oil constituents

Essential oils have been used to enhance the penetration and absorption of various substances through the skin. Indeed, scientists have observed this effect of essential oils for decades in relation to the transdermal delivery of drugs. Knowing this, synthetic chemicals—some of which are known hormone disruptors—are likely to penetrate through the skin at a higher rate when combined with essential oils.

Terpenes are the most common class of constituent found within essential oils and they are known to acts as penetration enhancers of multiple substances (vitamins, drugs, phytocompounds, etc.). Some of these individual terpenes have been explored for their ability to act as penetration enhancers. It is also possible that essential oils that contain multiple penetration-enhancing constituents—like tea tree and lavender—could possess a synergistic effect.

Lavender essential oil itself is a known penetration enhancer. Looking at the major components in lavender we find that the following are known penetration enhancers:

Tea tree essential oil also contains constituents that enhance the penetration of other ingredients or chemicals through the skin:

These lists are far from inclusive of all constituents in these two oils that increase the penetration of other substances through the skin.

Endocrine-disrupting chemicals in the products

A more plausible answer for the link between products that contain essential oils and PG or PT is interactions with other known hormone-disrupting chemicals present in the products. Many commercial personal care products (shampoo contains parabens and phthalates, which disrupt hormone activity) and colognes (many contain phthalates that disrupt hormone function) are a smorgasbord of harmful chemicals. Not to mention that essential oils may react with the chemicals (like bisphenol A, a known hormone disruptor) in the plastic containers of these products and cause them to leach into the product. Application of the product to the skin leads to absorption of both the plastic container chemicals and the synthetic chemical ingredients in the product.

While ingredients in wash-off products like shampoo and soaps have minimal contact with the skin, repeated exposure to these chemicals can have a cumulative effect. This is particularly true if the chemicals are being absorbed at a higher rate because the product includes lavender or tea tree essential oil. Colognes and perfumes are often sprayed directly on the skin and can have a higher absorption rate as a leave-on product.

In reality, exposure to hormone-disrupting chemicals is pervasive today because they are found in our water, air, clothes, food, furniture, vehicles, household cleaners, industrial chemicals, cosmetics, and personal care products. Indeed, one study found that infants are born with a tremendous toxic burden—an average of 200 chemicals present in umbilical cord blood at birth. Exposure to additional hormone-disrupting chemicals that are absorbed at a higher rate due to the presence of essential oils may have simply been the tipping point to trigger PG or PT.

The evidence-based and logical conclusion

Dozens of clinical trials using lavender or tea tree, combined with anecdotal use among millions of children, has not reported a statistically significant amount of estrogenic activity or hormone disruption for these two oils. We are each biologically unique and will respond to different substances uniquely. Most people can eat watermelon, but some have their throat itch and close if they do. Some children can eat peanuts, but to others, peanuts represent a threat to their life. Even among natural products, you will have a very small number of people that respond adversely or experience undesirable effects.

The presumed link to essential oils and hormone disruption in these studies is far from proven and frequently based on poor science and flawed methodology. The observations do not prove definitively PT or PG was caused by essential oils. This has been grossly overstated and aggrandized by the media. What we can learn from these studies is that consumers should be more selective about their products. They should choose natural products and products with essential oils that do not contain hormone-disrupting chemicals. Unfortunately, this is a major trend among companies selling soaps, lotions, shampoos, and other personal care products to capitalize on the growing essential oil industry.

The bottom line is you can still use tea tree and lavender essential oils on your children when diluted appropriately. With anything in medicine or health, the risks versus the benefits have to be weighed. And in this case, the vast whole-body benefits of these two essential oils far outweigh the minimal and rare risks that are far from proven.

Six Amazing Facts About the Sense of Smell (Olfaction)

Aromatherapy has captured the senses, especially the sense of smell, for centuries. From pampering Egyptian pharaohs to the anointing oil of spices mentioned in the Bible, majestic botanical essences have been highly esteemed and prized throughout history. Aromatic essences have also been an integral part of the healing systems of multiple ancient and modern cultures. So, what is all the fuss? Why have aromatic essences and essential oils stood the test of time? It may be partly related to the most powerful sense human beings possess—the sense of smell.

The sense of smell is vital to human health, allowing humans to identify food, mates, and predators, and detect pleasure and danger (e.g. smoke from a fire or harmful chemicals). Olfaction is the sensory receptors that form the sense of smell. Odor molecules travel to specific sites (olfactory epithelium) and bind to olfactory receptors located in the nasal cavity. Once bound to olfactory cell receptors, intensified signals are transmitted via the olfactory bulb (lying inside the nose and extending to two important areas of the brain: the amygdala and hippocampus) that rapidly reach the limbic area of the brain.

The limbic system is responsible for controlling emotions, memory, learning, instinct, and motivation. In addition, it is involved in sleep, libido, appetite, cardiovascular regulation, breathing, and hormone balance. Through this system, the aroma of essential oils can influence multiple physiological responses to hormones and neurotransmitters in the body.

Here are six fascinating and amazing facts about the sense of smell in humans.

The sense of smell is considered 10,000 times more potent than taste. Other senses like touch, taste, sight, and hearing must travel through the body via neurons in the peripheral nervous system and the spinal cord before reaching the brain (central nervous system). The olfactory response is immediate because of its direct link to the brain. Indeed, this is the only location where the central nervous system is directly exposed to the environment. Direct access to the brain means more rapid and substantial effects.

The sense of smell is the only sense directly connected to the brain. Unlike other senses, that must rely on neuronal communication from the peripheral to the central nervous system to operate efficiently, the sense of smell has a direct link to the central nervous system. Any disruptions in communication from the peripheral nervous system to the central nervous system can diminish these senses. As stated earlier, the olfactory bulb receives odor molecules first and then sends signals to the amygdala and hippocampus, which are strongly linked to emotions and memory. The other senses don’t pass through these areas of the brain, showing us the unique influence odors and smell have on human emotions and memories.

Females use the sense of smell to find a mate. Men and women are attracted to pheromones that the opposite sex produces. Men produce androstenol in fresh sweat (not exposed to oxygen), which is highly attractive to women. Research shows that women who are at the peak of fertility during their menstrual cycle prefer the smell of men with higher testosterone levels. Females also tend to prefer partners with different genes than their own according to scientists. A more diverse set of genes (major histocompatibility complex) produces offspring with a stronger immune system. In essence, women are sniffing out a mate with presumed healthy genes to ensure their offspring are healthy with a more robust immune system. Unfortunately, males don’t appear to have this same “superpower.”

Women have a greater sense of smell. Individuals have differing abilities to identify scents based on various factors. However, women outperform men when it comes to olfactory sensitivity that goes beyond social and cognitive differences between the genders. One study found that women on average have 43% more cells (50% when only neurons are counted) in their olfactory bulb when compared to men. This may account for their greater olfactory sensitivity and also contribute to their above mentioned “superpower” of sniffing out a mate.

Human Olfactory System: 1) Olfactory bulb, 2) Mitral cells, 3) bone, 4) nasal epithelium, 5) glomerulus, 6) olfactory receptor neurons

Olfactory receptors are not isolated to the nasal cavity. Olfactory receptors are chemical sensors responsible for your sense of smell. Scientists once believed that these receptors were isolated to the nasal cavity. That all changed when researchers at John Hopkin’s University School of Medicine (Maryland, USA) published a report reviewing discoveries of olfactory receptors on the kidneys, gastrointestinal tract, muscles, heart, pancreas, liver, lung, and skin. These fascinating findings help us understand that scent receptors play important roles in full human physiology and well-being.

Aromatherapy and scent memories. The sense of smell communicates directly with areas of the brain that store memories and govern emotions. You’ve likely walked into a house or shop and been captivated by a familiar aroma that instantly reminds of a past place, event, or person—think grandma’s perfume or cookies. You may have even felt strong emotions associated with this scent. These experiences are called scent memories and demonstrate how powerful odors are in relation to memories and emotions.

All things considered, the sense of smell is not only fascinating but an absolutely vital part of human well-being. It also shows us how potent aromas, like essential oils, can significantly influence our entire well-being by leveraging this influential sense. Maybe we need a new mantra of smell and be well.