Getting to the essence

One of the fastest-growing areas of alternative medicine is "essential oils."

Essential oils are at least something real; it's one step better than homeopathy, for example, which is charging money for water and/or sugar pills from which all biologically active compounds have been removed by serial dilution.  These oils are concentrated extracts of plants containing aromatic compounds, which the plants themselves make for a variety of reasons, including discouraging insects from eating the leaves, attracting pollinators, or encouraging animals to eat the fruits and disperse the seeds.

The claim is that these oils have positive health effects of all sorts, but when you start looking deeper, you find that a lot of times, what the essential oil companies have to say is pretty vague.  Here's one typical example, and a few representative quotes from the website:

• What are essential oils good for?  Since long ago, people have used essential oils and plant parts to improve their lives.  We’ve continued to explore their benefits today, finding that essential oils can be integrated into daily life for a plethora of purposes.
• What makes essential oils effective?...  The variety of essential oils allows you to naturally and effectively address your specific concerns.  With so many essential oils available, you can tailor them to your specific wants and needs rather than be forced to settle for a generic solution.  This makes essential oils a popular choice for those looking for the best natural solutions in the modern era.  The verstaility [sic] of essential oils is part of what has made them so popular in recent years.  People love that they can use essential oils for a variety of tasks, without having to buy multiple products.
• How do you use essential oils effectively?  Rest assured that you don’t have to be an expert to enjoy the wide array of benefits that essential oils offer.  All you really need is a basic understanding of how to apply essential oils safely and simply as part of your daily routine.

So, in essence *rimshot* -- oils are good because they've been used by people for a long time, they're all-natural, and they smell nice.  We know this because... um... reasons.  Each one is useful for something different, because they're so versatile.

[Image licensed under the Creative Commons Stephanie (strph) from Oklahoma City, USA, Teatreeoil, CC BY-SA 2.0]

The problem is, there's little scientific support for the claim that they'll accomplish anything but making you smell nice.  The site HealthLine has a page on essential oils, and you can tell they really really want to say how great they are, but can't quite find a way to do so without lying outright.  Over and over, they say things like this:

• It’s thought that certain application methods can improve absorption, such as applying with heat or to different areas of the body.  However, research in this area is lacking.
• [S]ome people claim that essential oils can exert a physical effect on your body.  However, this has yet to be confirmed in studies.
• Despite their widespread use, little is known about the ability of essential oils to treat certain health conditions.
• [D]ue to the scents of the compounds, it’s hard to conduct blinded studies and rule out biases.  Thus, many reviews on the stress- and anxiety-relieving effects of essential oils have been inconclusive.

Even so, HealthLine has a list of particular oils and what they can be used for -- which is more than a little disingenuous.

The problem is, we now know that beyond essential oils probably not doing anything positive for your health -- they can also be dangerous.

A study that came out a couple of weeks ago in the journal Epilepsy Research looked at a group of seizure sufferers in India, and found something staggering.  Here's a quote from The Academic Times that summarizes what they discovered:

[P]atients at four South Indian hospitals who had a seizure were evaluated for the use of camphor and eucalyptus essential oils.  Analyzing 350 seizure cases that spanned a four-year period, researchers found that 15.7%, or the seizures of 55 of the patients, may have been induced by the inhalation, ingestion, or topical use of essential oils.

Now, if you're gonna shout at me that this is correlation, not causation -- that the oil use may have been present in the patients, but not caused the seizures -- check out the next bit:

The patients were asked to stop their exposure to these essential oils and the products that contained them.  The researchers then followed up with the patients for a period of 1-3 years to monitor any recurrence of seizures.  All of the non-epileptic patients had been treated with anti-seizure medication, but for only two to four weeks following their first seizure, and none of them had a recurrence of seizures in the entire 1-3 year monitoring period after stopping their exposure to essential oils.  And 94% of the epileptic patients also remained seizure-free during the follow-up period.

Not proof, but certainly mighty suggestive.

A couple of years ago the journal Evidence-Based Complementary and Alternative Medicine published an article describing a comprehensive overview of essential oils and their connection to seizures.  The results: some essential oils have potential uses as anticonvulsants, but a much longer list have been associated with causing seizures.  Which, if you know any chemistry, is exactly what you'd expect; each essential oil contains a different set of compounds, so each one is going to interact with your body differently, and carry with it its own set of potential benefits and risks.  

But that's not what the people selling essential oils tell you.  Their claim is that they're all beneficial, then wave their hands around when you ask them how they know this.  (This is called the package-deal fallacy, and is exactly the same mistake a lot of anti-GMO people make; they say "GMO = bad" without acknowledging that since clearly all genes don't do the same thing, implanting said genes in other organisms isn't going to have the same effect for each, good or bad.)

And one other thing: if an alternative health practice is getting the suspicious side-eye from Evidence-Based Complementary and Alternative Medicine -- which I'd expect to be biased toward stuff like this -- it's worth listening to.

So if you're using essential oils, it might be prudent to stop.  Or at least investigate what, if anything, scientists know about the specific essential oil you like to use.  The vast majority of evidence is that other than smelling nice, they're probably not doing much for you, and there is an increasing body of data suggesting that some of them have a real potential for dangerous side-effects.

I'll just end with a quote from the inimitable Tim Minchin, who in his brilliant monologue/poem "Storm," says, "There's a name for alternative medicine that works.  It's called... medicine."

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When people think of mass extinctions, the one that usually comes to mind first is the Cretaceous-Tertiary Extinction of 66 million years ago, the one that wiped out all the non-avian dinosaurs and a good many species of other types.  It certainly was massive -- current estimates are that it killed between fifty and sixty percent of the species alive at the time -- but it was far from the biggest.

The largest mass extinction ever took place 251 million years ago, and it destroyed over ninety percent of life on Earth, taking out whole taxa and changing the direction of evolution permanently.  But what could cause a disaster on this scale?

In When Life Nearly Died: The Greatest Mass Extinction of All Time, University of Bristol paleontologist Michael Benton describes an event so catastrophic that it beggars the imagination.  Following researchers to outcrops of rock from the time of the extinction, he looks at what was lost -- trilobites, horn corals, sea scorpions, and blastoids (a starfish relative) vanished completely, but no group was without losses.  Even terrestrial vertebrates, who made it through the bottleneck and proceeded to kind of take over, had losses on the order of seventy percent.

He goes through the possible causes for the extinction, along with the evidence for each, along the way painting a terrifying picture of a world that very nearly became uninhabited.  It's a grim but fascinating story, and Benton's expertise and clarity of writing makes it a brilliant read.

[Note: if you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!]

Spice of life

In many places, people argue vehemently about politics, religion, or culture.  In my home place of southern Louisiana, the hill people will die on is whose grandma had the best gumbo recipe.

My mom was 100% Cajun, from a little town near Raceland, Louisiana, south of New Orleans.  Because of that, I grew up with amazing food, both in quality and quantity.  Jambalaya, hush puppies, oyster po'boys, courtbillon, boudin (Cajun sausage), crawfish, fried catfish...

*brief pause to stop drooling*

In Cajun cuisine, the four food groups are onions, pepper, garlic, and grease.  Just about every recipe you pick up begins with, "First, you make a roux."  It's rich, spicy, and intensely flavored, but to say it's "calorie-dense" is a massive understatement.  Fortunately for me, I was born with a fast metabolism, but most Cajun food is not what I'd call diet-friendly.

I learned to cook as a teenager, mostly because I love to eat, and I didn't want when I moved away from home to go from my mom's phenomenal cooking to eating canned ravioli.  So I've become the chief cook in our family, and both our sons also learned to cook as teens, for much the same reasons that I did.  When I talk to my younger son, who lives in Houston, and he tells me he's got a pot of chicken gumbo simmering on the stove, it positively warms my heart.

His grandma's recipe, of course.

I've wondered for a while why Cajun food is so spicy.  And, by extension, why some cuisines are so bland.  My wife is Jewish, and she actually came up with a recipe for Cajun matzoh balls so that I would agree to eat them.  British cooking is notorious in that regard, although I will say that when I was in England I couldn't get enough of fish & chips, preferably washed down with a pint of stout.  On the other hand, the "mushy peas" I had when we were in Durham is an experience I'm not anxious to repeat.  

Even Cajun food, however, doesn't hold a candle to the spiciness you find in southeast Asia.  My first time at a Thai restaurant, I was given the choice of 1 through 5 for spiciness, and I figured, "Hell, I'm Cajun, I'm tough" and went with a 3.

And spent the entire meal guzzling iced tea to put the fire out.  Heaven alone knows how anyone eats a "5" without spontaneously combusting.

I got to visit Malaysia a few years ago, and they have a sauce there called "sambal oelek" which is Malay for "bottle full of lava."  If you are ever fortunate enough to visit there, and it's offered to you, be brave -- but use it in moderation.  (And by "in moderation" I mean "one drop.")

[Image licensed under the Creative Commons Mark Levisay from Ruckersville, VA, USA, Hot peppers for jelly. Clockwise from bottom left; habaneros, hot Portugal, hot lemon, serrano, poblano, cajun bell & jalapeno, CC BY 2.0]

When I lived in Seattle, I went to a talk by a food scientist about the use of spices in different cultures, and he was of the opinion that the heat of a cuisine is directly proportional to the heat of the climate.  Many spices, he claimed, contain essential oils that are bactericidal, and also might cover up the taste of food that was a little past its expiration date.  So cold climates, like Scandinavia, with less need for spices to prevent and/or mask spoilage, have less spicy cuisines than (for example) India.

It seemed like a reasonable hypothesis, and most of us left the talk thinking, "Huh, who knew?  That's pretty cool."  But a study in Nature last week demonstrated that -- like a good many common-sense notions of how the world works -- it doesn't line up with reality.

Lindell Bromham, Alexander Skeels, Hilde Schneemann, Russell Dinnage, and Xia Hua (of Australian National University) did an exhaustive analysis of cuisines around the world, testing both that hypothesis and also the alternate conjecture that spicy cuisines arise only where the plants that produce those spices grow easily -- and found, surprisingly, that neither model accurately predicts food spiciness.  The authors write:

Spicier food in hot countries has been explained in terms of natural selection on human cultures, with spices with antimicrobial effects considered to be an adaptation to increased risk of foodborne infection.  However, correlations between culture and environment are difficult to interpret, because many cultural traits are inherited together from shared ancestors, neighbouring cultures are exposed to similar conditions, and many cultural and environmental variables show strong covariation.  Here, using a global dataset of 33,750 recipes from 70 cuisines containing 93 different spices, we demonstrate that variation in spice use is not explained by temperature and that spice use cannot be accounted for by diversity of cultures, plants, crops or naturally occurring spices.

The negative results here are as interesting as the conjectures themselves, and leave us with a bit of a puzzle.  The authors found a weak correlation between spice use and wealth -- many spices, even today with commercial farm production, are expensive -- but that doesn't really account for the distribution either, because most areas are a mix of wealthy and poor and all gradations in between, and in a particular region people mostly eat the same kinds of food (although of course there are differences both in quality and quantity of food available to different socioeconomic strata).

The end result is another unsatisfying example of "we don't really know why, but it seems to be complicated."  I've heard it suggested that once a cuisine is established with a particular repertoire of spices, babies learn to tolerate those flavors because some of the essential oils are passed along to the infant in breast milk.  (The obvious example is garlic -- people who eat a lot of garlic will find that their sweat eventually smells of it, although at that point it might be more obvious to their friends and family than it is to them.)  Even if that's true, it might explain the persistence of particular sets of spices in a culture, but doesn't explain why they got there in the first place.

All of which is fascinating, not only because I'm a foodie but because of my background in science.  It's always good to look at your assumptions about the world, because something that "seems right" is likely to go unquestioned in your mind.  It's why we have the scientific method; it's a way of rigorously testing claims, so that our biases in either direction can be analyzed in the clear light of data and inductive reasoning.

Anyhow, now I'm hungry.  Maybe I'll fix some scrambled eggs for breakfast, but only if I'm not out of hot sauce.  There is no point to scrambled eggs without hot sauce.  Although I think I'll pass on the sambal oelek.  Even I have my limits.

Oh, and it's my grandma.  My grandma clearly had the best gumbo recipe.  Thanks for asking.

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Back when I taught Environmental Science, I used to spend at least one period addressing something that I saw as a gigantic hole in students' knowledge of their own world: where the common stuff in their lives came from.  Take an everyday object -- like a sink.  What metals are the faucet, handles, and fittings made of?  Where did those metals come from, and how are they refined?  What about the ceramic of the bowl, the pigments in the enamel on the surface, the flexible plastic of the washers?  All of those substances came from somewhere -- and took a long road to get where they ended up.

Along those same lines, there are a lot of questions about those same substances that never occur to us.  Why is the elastic of a rubber band stretchy?  Why is glass transparent?  Why is a polished metal surface reflective, but a polished wooden surface isn't?  Why does the rubber on the soles of your running shoes grip -- but the grip worsens when they're wet, and vanishes entirely when you step on ice?

If you're interested in these and other questions, this week's Skeptophilia book-of-the-week is for you.  In Stuff Matters: Exploring the Marvelous Materials that Shape Our Man-Made World, materials scientist Mark Miodownik takes a close look at the stuff that makes up our everyday lives, and explains why each substance we encounter has the characteristics it has.  So if you've ever wondered why duct tape makes things stick together and WD-40 makes them come apart, you've got to read Miodownik's book.

[Note: if you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!]

Food vibrations

Apparently, Australia being nonexistent and people selling homeopathic black holes weren't enough, so a friend and loyal reader of Skeptophilia sent me a link to a site called "iTOVi," which sells "nutritional scanners."

The website tells us that the scanner is designed to "provide a list of top oils and supplements your body has a response to."  How, you might ask?  Well, here's their explanation:

Our portable nutrition scanner allows you and your clients to receive personalized product responses at any time of day!  How? The  iTOVi scanner uses innovative and institutionally recognized technology to measure the body’s response to electronic frequencies.  The scanner records the body’s reaction to these frequencies and matches the user with products that have complimentary frequencies.

So we're on thin ice already, but it gets a lot thinner.  I went to the page on "technology" -- call me a doubter, but I always want to know how things work.  And I wasn't disappointed.  We're told that everything, biological and non-biological, vibrates at a particular frequency, including "supplements and essential oils."  The machine figures out your vibration with a technique that should sound vaguely familiar:

During an iTOVi scan the device passes small electrical currents through the skin to measure the body’s resistance to frequencies, each of which is the natural energy signature of various supplements and oils.  The passing of electrical frequencies induces a measurable response from the body which is then recorded and shown in the iTOVi report.

If you're thinking, "but... isn't that how a polygraph machine works?", you're spot-on.  Polygraph machines -- which, to be up front, are of dubious use in telling whether people are lying -- measure small changes in skin conductivity, which occur primarily because of the amount of sweat a person has on their skin.  Sweat, being weakly saline, is quite a good conductor; and since the theory is that a person would sweat more under conditions of emotional stress (such as lying), changes in skin conductivity could give interrogators a clue about someone's veracity.

A polygraph machine [Image courtesy of the Wikimedia Commons]

You may have noticed that nothing in the preceding paragraph mentions "frequencies."  That doesn't stop the iTOVi people, who claim that these conductivity changes are a clue to the body's "frequency," and they derive one from the other by means of an unspecified algorithm.  We're never given any specifics -- not even the number of Hertz we all should be shooting for.

Most of the places that blather on about "frequencies" (and "energies" and "vibrations" and "resonance") seem to think that the higher the frequency the better.  I did some digging and found the website "Vibrational Frequency 101," which I read, at great cost to the cells in my prefrontal cortex, which were screaming in agony by paragraph three.  It features passages like the following:

First off, we are not just our physical body {aka matter}. We are all made up of energy – all matter is – and bound together by an energy field. We’re talking atoms, protons, and neutrons…  This is science, people! 

So, everything vibrates with an energy. And, the higher the energy, the higher the frequency.  Positive feelings and thoughts evoke a higher frequency vs. negative feelings and thoughts evoke a lower frequency. 

The energy we’re made up of connects us to all living things and the universe.  When you really break it down, we are all just balls of energy walking the planet. 

Our energy is blocked when we experience negativity, fear, or you guessed it… unhealthy substances.  Think about it.  When you consume really unhealthy food, alcohol, or drugs, doesn’t your energy feel low, or dull or blocked?  Low vibrations mean a dampened energy field. It also means a disconnection to other things, the universe, and ourselves...  Plus, a constant negative state can lead to sickness and disease in the body.

For example, "fresh organic vegetables" supposedly have "high vibrations," while deep-fried food has "low vibrations."

Look.  You can say "this is science, people!" and "institutionally recognized technology" all day long, but until you can show me, using an oscilloscope, that kale is vibrating at 14,500 Hertz and KFC is vibrating at 7 Hertz, I'm calling bullshit.  Besides, if our food really is vibrating, shouldn't we be able to hear it?  You know, like kale emits this high-pitched whistle, and KFC a low, sad buzz, or something?  But despite listening carefully to my bowl of oatmeal this morning, I heard nothing but my wife sighing in resignation at her husband doing yet another ridiculous thing in the name of scientific research, and my dog wagging his tail, the latter presumably figuring that if I was doing something weird with my food, maybe it meant he was going to get some.

In short: the entire claim is nonsense.  You, and your organs, do have a natural (or resonant) frequency, because everything with mass does.  (Think of the natural swing rate of a kid on a swingset -- it's hard-to-impossible to make the swing oscillate at any other frequency.)  But all this means is that if your body is shaken at that frequency, it'll make (for example) your spleen vibrate, which sounds painful.  It has nothing to do with "feelings" or "negativity" or, for fuck's sake, "essential oils."

And, in fact, if you really believe that higher frequencies are better for you, let's run this experiment.  You listen to a piccolo playing a high D at full volume for an hour, and I'll listen to a cello playing a low note.  Let's see who comes away from the experience with a headache.

So about iTOVi: save your money.  The whole claim is nonsense, as you might figure out if you see the notorious disclaimer on their page, "This device is not meant to treat, cure, or diagnose any illness, nor should it be construed as medical advice."  Which, as always, is a good indicator that what it's proposing is horseshit.

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This week's Featured Book on Skeptophilia:

This week I'm featuring a classic: Carl Sagan's The Demon-Haunted World: Science as a Candle in the Dark.  Sagan, famous for his work on the series Cosmos, here addresses the topics of pseudoscience, skepticism, credulity, and why it matters -- even to laypeople.  Lucid, sometimes funny, always fascinating.

Ebola, epidemics, and the danger of making decisions out of fear

The news has been filled in the last couple of weeks with stories about the ongoing epidemic of Ebola fever in west Africa.  And certainly, there's a lot here that's newsworthy.  An emerging virus, long known for lightning-fast outbreaks that killed whole villages deep in the jungle and then disappeared as fast as it came, has finally appeared in two large cities, Conakry, Guinea and Monrovia, Liberia.  The disease itself is terrifying; it has a mortality rate of between 60% and 90%, depending on the strain, and kills victims when their blood stops clotting, causing them to "bleed out."

Which, unfortunately, is exactly what it sounds like, and about which I won't say anything further out of respect for my more sensitive readers.

The Ebola virus [image courtesy of the Wikimedia Commons]

This epidemic has two of the features that tend to make people overestimate risk: (1) it's gruesome; and (2) it's novel.  We react most strongly to things that are new, unfamiliar, and scary, and Ebola certainly qualifies.  And it is a regrettable feature of human nature that when our fear centers are engaged, we make dumb decisions.

Let's start with the desperate desire on the part of people who are scared by the virus to protect themselves against it, although the current state of affairs is that there is no vaccine, and no way to prevent catching it except by avoiding close contact with ill individuals.  This hasn't stopped the hucksters from seeing this as an opportunity to extract money from the gullible.  Starting with the site Essential Oils For the Win!, which makes the bizarre claim that we "shouldn't be scared of Ebola" because "it can be treated with the proper essential oil."

Well, it's true that there's probably no real reason to be scared of Ebola unless you're planning on a visit to west Africa, but I would invite the owner of this website to go there himself armed only with a vial of lavender oil, and see how confident he feels then.  That the author of the website has a slim grasp of science, and probably reality as well, is reinforced by the diagram wherein we're shown that essential oils work because unlike conventional medicines, they are good at "penetrating cell walls."

So it's reassuring to know that your tomato plants and petunias won't get Ebola.  As for us, being animals, our cells don't even have cell walls, so I'm thinking that I'd rather see what the actual scientists come up with.

Which definitely does not include the homeopaths, who are also weighing in.  No worries, they say... according to an article at The Daily Kos, they already have their "remedies" at the ready!

Dr. Gail Derin studied the symptoms of Ebola Zaire, the most deadly of the three that can infect human beings. Dr. Vickie Menear, M.D. and homeopath, found that the remedy that most closely fit the symptoms of the 1914 "flu" virus, Crolatus horridus, also fits the Ebola virus nearly 95% symptom-wise! Thanks go to these doctors for coming up with the following remedies:
1. Crolatus horridus (rattlesnake venom) 2. Bothrops (yellow viper) 3. Lachesis (bushmaster snake) 4. Phosphorus 5. Mercurius Corrosivus

Yup.  Here's their logic: because the venom of "Crolatus horridus" is 95% fatal, and so was the Spanish flu, and so is Ebola Zaire, the venom must be useful for treating Ebola.  Only, of course, if you dilute it until all the venom is gone.

I only have three objections to this:

1. I'm assuming you're talking about the timber rattlesnake, which is in the genus "Crotalus," not "Crolatus."  And the Spanish flu occurred in 1918, not 1914.  But those may be minor points.
2. Many other things have a very high fatality rate, including gunshots to the head.  Does this mean you could also add a sixth "remedy" for Ebola, Essentius Leadus Bulletus, made by shaking up bullets in water and diluting it a gazillion times?
3. Are you people insane?

 The fear tactics didn't stop with loony cures, though; the politicians began to weigh in, and (of course) attempt use the whole thing to score political capital.  And once again, they are targeting people who are thinking with their adrenal glands rather than their brains.  No one is as good at that as the inimitable Michele Bachmann, who instead of fading into richly-deserved obscurity, has kept herself center stage with commentary like this:

People from Yemen, Iran, Iraq and other terrorist nations are making their way up through America’s southern border because they see that it’s a green light, they can easily get in.  Not only people with potentially terrorist activities, but also very dangerous weapons are going to cross our border in addition to very dangerous drugs, and also life-threatening diseases, potentially including Ebola and other diseases like that... 

Now President Obama is trying to bring all of those foreign nationals, those illegal aliens to the country and he has said that he will put them in the foster care system.  That's more kids that you can see how - we can't imagine doing this, but if you have a hospital and they are going to get millions of dollars in government grants if they can conduct medical research on somebody, and a Ward of the state can't say 'no,' a little kid can't say 'no' if they're a Ward of the state; so here you could have this institution getting millions of dollars from our government to do medical experimentation and a kid can't even say 'no.'  It's sick.

So, let's see if we can parse this.  People from the Middle East are coming in across the border between the United States in Mexico, and they did so by coming via Liberia, where they picked up Ebola, and they're going to pass that disease along to innocent Americans, but some of the kids got infected along the way, and now President Obama is going to place them in medical facilities where they will be experimented upon in unimaginably cruel ways.

Is it just me, or does Michele Bachmann seem to have a quarter-cup of PopRocks where the rest of us have a brain?

 What I find ironic, here, is that people are flying into a panic over a disease that (1) is rather hard to catch, and (2) has caused only 500 deaths thus far.  I say "only" to highlight the contrast with another disease, measles -- which according to the World Health Organization, killed 122,000 people in 2012 and is set to break that record this year, despite the fact that it is completely preventable by a safe and effective vaccine.

Oh, but we've all heard of measles.  So it can't be that bad, right?

And if you are still unconvinced that vaccination is the best way to go -- swayed, perhaps, by claims that the most recent measles outbreaks in the United States were among the vaccinated -- take a look at this brilliant explanation over at The LymphoSite, which explains why even if vaccines have some side effects and sometimes do not work, we still should all be vaccinated.

All of which re-emphasizes that we're better off considering actual facts, and listening to actual scientists, rather than falling prey to hucksters or listening to loons like Michele Bachmann.  Which means engaging our brains, and trying to think past our fears.

Smell-o-therapy

I'd always wondered how "aromatherapy" was supposed to work.  I mean, I like nice-smelling things as much as the next guy, but treating diseases by having you smell something just always seemed a little weird to me.  But I'd never really looked into it.

And then a friend sent me this page, wherein we find that it all has to do with "frequencies."

I shoulda known.

Frequency is one of the most misused words in all of woo-woo.  So let's get the definition straight right from the get-go, okay?  Frequency is a measurement of the rate of vibration of anything that is exhibiting rotation, oscillation, vibration, or simple harmonic motion, and is measured by counting the number of cycles completed per second.  A hertz is the standard unit of frequency, and is equal to one cycle per second -- so in a pendulum clock that is keeping good time, the pendulum is swinging at exactly one hertz.  The frequency of sound waves audible to the human ear runs from about 20 hertz to about 18,000 hertz (18 kilohertz).  The electromagnetic spectrum has a much wider range, with the "low" end (radio waves) running all the way down to one hertz or lower, and the "high" end (gamma rays) up into the range of 10²⁴ hertz.  The bit of the electromagnetic spectrum that our eyes are sensitive to -- the familiar rainbow of visible light -- runs in the vicinity of 10¹⁴ hertz, with red having the lowest frequency (around 4 x 10¹⁴ hertz) and violet the highest (around 8 x 10¹⁴ hertz).

All right, thus endeth the science lesson for today.  Let's look at aromatherapy oils, okay?  Hold onto your hats, because we won't be re-entering the realm of science for a while.

The site I linked above begins thusly:

The effectiveness of aromatherapy essential oils cannot be fully understood without some discussion of their frequency or vibration. Frequency is a measurable rate of electrical energy that is constant between any two points. Every living thing has an electrical frequency. Robert O. Becker, M.D., documents the electrical frequency of the human body in his book, The Body Electric. A "frequency generator" was developed in the early 1020's [sic] by Royal Raymond Rife, M.D. He found that by using certain frequencies, he could destroy a cancer cell or virus. He found that these frequencies could prevent the development of disease, and others would destroy disease. Substances with higher frequency will destroy diseases of a lower frequency.

So, we already have:  (1) a typo that makes it sound like someone was developing electronic devices before the Norman Conquest of England; (2) a guy named "Royal Raymond Rife;" and (3) enough bullshit to fertilize a 50-acre cornfield.  Pretty good start for only one paragraph, don't you think?  But it gets better:

In one test, the frequency of two individuals – the first a 26 year old male and the second a 24 year old male – was measured at 66 MHz each. The first individual held a cup of coffee (without drinking any), and his frequency dropped to 58 MHz in 3 seconds. He put the coffee down and inhaled an aroma of essential oils. Within 21 seconds, his frequency had returned to 66 MHz. The second individual took a sip of coffee and his frequency dropped to 52 MHz in the same 3 seconds. However, no essential oils were used during the recovery time, and it took 3 days for his frequency to return to its initial 66 MHz. One surprising aspect of this study measured the influence that thoughts have on the body's electrical frequency.

Me, I usually vibrate faster after drinking coffee, especially given that I'm from Louisiana, where they don't consider it real coffee unless it's so strong you can stand a spoon upright in it.  I periodically have to replace my coffee mug because the coffee I make has eaten through the ceramic.

But I digress.

So what, then, is the "bioelectric frequency" of various familiar items?  I'm sure you wanted to know, and lo, they provide you with a handy chart:

Fundamental Frequencies of People and Things
(frequencies given in Megahertz)

• Healthy Human Brain...........................................................71-90
• Healthy Human Body (overall).............................................62-68
  • When you have cold symptoms........................................58
  • When you have flu symptoms...........................................57
  • When you have candida infection.....................................55
  • When you have Epstein Barr Syndrome...........................52
  • When you have cancer......................................................42
  • When one begins to die.....................................................25
• Processed or Canned Foods...........................................................0
• Fresh Produce (depending on how fresh)................................10-15
• Dry Herbs................................................................................12-22
• Fresh Herbs.............................................................................20-27
• Therapeutic Grade Essential Oils......................................52-320

So let's see -- canned tuna isn't vibrating at all, and infections of various sorts make you vibrate slower until finally you die when you reach 25 megahertz.  Presumably after you die you continue to decrease in vibration until you reach the canned-tuna stage.

And last, we find out two important things: (1) if you pray over your aromatherapy oils, they vibrate faster; and (2) exposing the body to the highest frequencies causes "spiritual changes."  Thus, I suppose irradiating yourself with gamma rays would just make you experience all sorts of spiritual growth, or possibly just turn you into The Incredible Hulk.  Which, now that I come to think of it, is a spiritual change of a rather impressive magnitude.

So once again, we have some people making unsubstantiated health claims that could potentially convince someone with a life-threatening disease to abandon conventional therapy for sitting around inhaling rose oil.  And despite the disclaimer at the bottom of the page -- "These statements have not been evaluated by the Food and Drug Administration.  These products are not intended to diagnose, treat, cure, or prevent any disease," it sounds like that is exactly what they are suggesting.  And when you read the bit that comes immediately before the disclaimer, it becomes even clearer:

The penetrating characteristic of essential oils greatly enhances their ability to be effective. Essential oils will penetrate into the body when applied to the skin. Placed on the foot they will be distributed to every cell in the body in 21 minutes. They will even penetrate a finger or toe nail to treat fungus underneath.

Essential oils stay in the body about 20 minutes to 2 hours and leave no residuals. The effects and frequency are accumulative when the mental attitude changes. We must have a desire to change and work on it or the old programming will keep coming back. Oils are a precursor to set up stage for action and a catalyst to do the work (the blood stream). Oils go where the need is present and are activated in that area. Testing on the thyroid, heart and pancreas showed that the oils reached these organs in 3 seconds! When layered, one oil applied over another, it is faster. The body absorbs the oils fastest by inhalation and second fastest by applying to the feet or ears. The oils also cross the blood brain barrier; they piggy-back the energy waves to get into the cells.

All the essential oils deliver cell wall penetrating oxygen, and it is the unhealthy cells that need the oxygen for the road back to health. When the cell wall thickens, oxygen can’t get in – life expectancy of a cell is 120 days to 4 months). Cells divide making 2 duplicate cells, and if it is diseased, it will make 2 new diseased cells. When we stop the mutation of the cells and create healthy cells, we stop the disease. Therapeutic grade essential oils can restore cells to normal in 7 seconds.

Do not wait until you have the “right” essential oil before administering to a symptom. You cannot be doing it wrong if you use any of the oils for any symptom! When an oil causes discomfort, it is because it is pulling toxins, chemical, heavy metals, poisons, parasites and mucus from the system. Either stop taking the oils for a short time to make sure your body isn’t eliminating too fast or dilute the oils with V-6 Mixing Oil until the body catches up with the releasing. These toxins go back into the system if they cannot be released. If a person does not like the smell of an oil, it is usually because of an acidic condition.

How is this not a claim to "diagnose, treat, cure, or prevent disease?"

Once again, I think the thing we need to cure first here is ignorance of biological science.  Given a basic background in biology -- I mean, come on, the sophomores in my Introductory Biology class could debunk this stuff -- anyone would be able to recognize the falsity of these claims.  And we wouldn't have to get the FDA involved, because no one would buy the "essential oils" unless they wanted to use them for the one purpose they have -- to make your house smell better.