Tuesday, 17 May 2016

Meridians, acupuncture, onions and Bullshit: Why putting onions in your sock won't cure anything.

I'm sure that anyone with a social media account is by now familiar with this form of click-bait headline:

"He/she did this. What happened next will amaze you."

I'm also sure, like me, most of you scroll right past these stories without too much thought. A colleague of mine clearly doesn't as she recently recommended a remedy to me which she had come across on the site Boredom Therapy. The stupidity of the post is staggering. Just take a look at the headline and the main photo.

"She Put Onions In Her Socks Before Going To Sleep. When You See Why, You’ll Realize It’s Brilliant."

Will I? Really? Will I? Yep, it's stupid alright. Let's see why....

The article begins:
"For years, people sick with colds or the flu have gone to bed with sliced onions in their socks and woke up feeling refreshed. This sounds absurd, but there is a reason for it.... There are more than 7,000 nerve endings on the bottom of your feet that connect to the rest of you body. These nerves have been a major focal point of Eastern medicine for thousands of years."
 "More than 7000..."? Technically that's correct, there are more than 7,000, there are actually MILLIONS of nerve endings in the feet and of course, they connect to other parts of the body. I don't argue that these areas of the body have been a focus of Eastern medicine, but this doesn't validate those practices.

The particular practice that the author of the piece seems to be referring to is that of reflexology. The manipulation of the feet in order of solve conditions ailing other areas of the body. You'll probably be unsurprised to learn that clinical studies have thus far shown reflexology to be no more effective than placebo. In 2010, Edzard Ernst conducted a systematic review of 23 clinical trials for medical journal Maturitas, he concluded:
"It is concluded that the best clinical evidence does not demonstrate convincingly reflexology to be an effective treatment for any medical condition." (Ernst et al, 2010)
As an aside, when alt-med supporters bang on about the effectiveness of ancient Eastern medicine the first thing I often ask them is why, if that is the case, modern western medicine is so in demand in the East?

Website "Healthy, Wild and Free" (no it's not that kind of website) attempt to explain the connection between the feet and your nervous system:
"They (nerve endings) are very powerful electrical circuits within the body and are often dormant because we wear shoes and don’t get accupuncture done to help the meridians or nerves in any way.... One of the coolest ways to open up these electrical pathways (meridians) and to help purify your internal organs without doing anything internal (diet related) is to cut up onions or garlic and put them in your socks (at the bottom part of your feet) while sleeping"
This is massively incorrect. The nervous system ISN'T an electrical circuit. Due to gaps between nerve cells called Synaptic clefts, an electrical signal doesn't run directly from a nerve ending to the target receptor. The health research board explains further:

"The arrival of a signal called an impulse triggers the release of special chemicals into the gap. These chemicals,neurotransmitters , diffuse across the gap locking into the receptor molecules in the target cell membrane, causing it to ‘switch on’.
It switches off when no more neurotransmitters are released and those that were previously released have been broken down by an enzyme in the gap. The broken down neurotransmitters are then reabsorbed into the synaptic knob.
Because the transmission between neurons is a chemical process, it is possible to alter signaling between nerve cells by using chemical substances."
-Health Research Board (2013)

Further to that, this pretty much rules out any effect of placing an onion against the skin other than the job the nervous system is designed to do, i.e-passing the sensation to the brain. Meridians don't exist, we can be pretty sure of this as the practice of acupuncture, which also rests on the existence of meridians has never been shown to be more effective than placebo:

"Controlled clinical trials of actual acupuncture ( typically have three arms: a control group with no intervention or standard treatment, a sham-acupuncture group (needles are placed but in the “wrong” locations or not deep enough), and a real acupuncture group. Most of such trials, for any intervention including pain, nausea, addiction, and others, show no difference between the sham-acupuncture group and the true acupuncture group. They typically do show improved outcome in both acupuncture groups over the no-intervention group, but this is typical of all clinical trials and is clearly due to placebo-type effects." - Science Based Medicine
The fact that the sham-acupuncture group showed the same improvements as the real acupuncture shows that placement of the needles was irrelevant, hence either the whole body is a giant meridian, the researchers accidentally hit other meridians or that meridians don't exist.

Anyway, let's say I grant that these Eastern medicine techniques are more effective than placebo for a moment, which they aren't. Why would replacing the message element of reflexology with a root vegetable provide any benefit? Well, it's all due to the special properties of the humble onion you see:

"Onions, also a key ingredient in Eastern medicine, are naturally anti-bacterial. "

Shockingly, this claim actually has some basis in science. A study in 1997 by JH Kim, showed that onions did show limited antibacterial properties when placed in cultures of oral bacteria. This effect was however significantly reduced in the presence of alkaline and at temperatures of 37^0 C. The problem here being that temperature is pretty significant. It's the average body temperature of a human being.

Let's grant that the onion does have antibacterial qualities and that this holds in a sock, this effect is only going to apply in pretty much the area the onion is in contact with the skin being pretty much impermeable to any chemicals from the onion and the initial input to the nervous system being an electrical impulse triggering a chain of chemical processes. This makes the next claim made by article seem utterly ludicrous:
"Fans of this treatment claim that going to sleep with the onion on your feet releases your body’s toxins into the root vegetable, leaving you feeling healthy and refreshed in the morning."
Do they? Have they bothered to say, test this? Do they have any mechanism by which this could work? The skin is pretty impermeable to most chemicals, and there's no evidence of toxins being able to pass from the body to the environment via the skin. Couple this with the fact that the body already has a pretty good detoxification system: it's called the liver. Add in with the body's natural excretory system and it seems unnecessary to accessorize with salad vegetables to perform these tasks.

With all this in mind, let's return to the initial claim: Can this help with a cold or flu? The author of the piece simply hasn't justified this claim. Even if we accept that onions have the properties described, none of that applies to colds or flu: these are viruses, not bacteria or toxins! Viruses are infectious agents which replicate inside the cells of its host. How exactly would an onion in a sock draw viruses from cells in a host's lungs?

Let's see if any other sites can make some sense of these absurd claims. Alt-Med sales site "Healthy Bliss" just offers more nonsense on the topic:
"...with the body being so clean, the fumes from the onion could theoretically be absorbed through the skin and pass through the body more quickly, and perhaps eliminate internal bad bacteria or even parasites."
"Theorectically" I don't think the author of this piece has a damn clue what the word theory means (or how to spell it. It's "theoretically"), I'll offer a hint. It doesn't mean "Any old tripe that justifies something I want to believe..." Also "fumes"? No fumes pass through the skin. by the very definition of the word ("...any smokelike or vaporous exhalation from matter..." Dictionary.com), fumes are something that is inhaled or exhaled.

In fact some brave soul at the website conducted "an experiment" testing the healing power of the sock/onion treatment. Forget all that you know about the scientific method, blinding, controls, and methodologies. Forget that personal anecdote isn't evidence. And forget the fact that the point of an experiment is to remove bias and subjectivity and enjoy the stupid.
"After about 30 minutes with the Onion Socks on, I started to feel distinct quivers in my calves and a twitch on my left side at the rib cage. In another 10 minutes, my eyes started to tear as if I had just cut an onion, although a much milder sensation but clearly a distinct tearing."
"AS IF" she'd just cut an onion? AS IF? You have just cut an onion. It's in your fucking sock, you moron!
"5 minutes after that, my boyfriend told me he had the taste of onion in his mouth!"

That's remarkable! It's almost as if the senses of taste and smell are intrinsically linked and your boyfriend can smell onion... BECAUSE IT'S IN YOUR FUCKING SOCK!

She describes the results of the first night of the "experiment":
"I felt tired and weak, the first day for me to feel that way, but I did feel better. I don’t think it was the placebo effect as I am very open to trying something and saying it doesn’t work."
You can't switch off the placebo effect, even if you are aware of it. Also, it sounds distinctly like she's not sure that she felt better at all.
"And the real reason why I think it worked is because 90% of my hay fever and allergy symptoms disappeared overnight!! I went through the whole day with no itchy eyes and no itchy nose and I think I sneezed only 2 times the entire day!! Now, that is no placebo effect!"

Again, she's no idea about the placebo effect. Also, I doubt she checked the pollen count that day. That could explain why her allergy symptoms were absent. I doubt she attempted to control for any of the variables that could affect the outcome of the experiment. Either that or she forgot to tell us about it. What she doesn't forget to do is try and sell us her latest book.

"For Dummies" A more apt title I never read.

Frankly, the only thing you are going to get from put onions in your socks is... well... extremely smelly socks and inedible onions. Let's be logical. If you have a cold or the flu, a few days of rest will usually leave you feeling better regardless of what root vegatable you sleep with.

On an unrelated note, a few people are asking me where I get my amazing skeptical prowess from. I will now share my secret.The answer is quite simple, I sleep with a copy of Carl Sagan's Demon Haunted world in my sock every night.