More of The Lost Symbol, Noetic Sciences, and the Pineal Gland

So, a little while back, I posted a bit on the so-called "Noetic Sciences" which feature in the new Dan Brown novel The Lost Symbol.  Briefly, the "Noetic Sciences" refers to research conducted by a group called the Institute for Noetic Sciences (IONS) which was founded by astronaut Edgar Mitchell to study parapsychology (think Ghostbusters).  While topics like "healing from a distance (with thought) and other "mind over matter" type ideas can be tested experimentally, there is no evidence suggesting that these things are possible.  Thus, institutes like IONS, which claim to be making progress on these fronts, get relegated to the categories of pseudoscience and quackery.
Anyway, my point here is not to beat up on IONS because I don't really know how much real science and how much pseudoscience is going on there. Rather I would like to try and correct some of the neuroscience myths that showed up as I was finishing The Lost Symbol.
One in particular I want to take issue with is a line toward the end of the book when the character Katherine Solomon describes the pineal gland:

“Perhaps you’ve heard… about the brain scans taken of yogis while they meditate? The human brain, in advanced states of focus, will physically create a waxlike substance from the pineal gland. This brain secretion is unlike anything else in the body. It has an incredible healing effect, can literally regenerate cells, and may be one of the reasons yogis live so long. This is real science, Robert. This substance has inconceivable properties and can be created only by a mind that has been highly tuned to a deeply focused state.”

Now, I know a lot of people have trouble realizing that Dan Brown writes FICTION, and so I think its important to relate that this claim about the pineal gland is false.  First, we know what the pineal body (aka pineal gland) is, and what it does.  And what it secretes is not some mysterious waxy substance that can magically heal people, but a hormone called melatonin, which, helps to regulate our circadian rhythms, otherwise known as our sleep/wake cycle.  Melatonin is not, as far as I know, "waxlike", nor can it cure leprosy (or anything else), nor is it "unlike anything else in the body".  What melatonin can do is tell you when you should be tired and go to sleep (in fact, for a long time, it was thought that the sleepiness you feel after thanksgiving dinner was caused by a large amount of tryptophan in the turkey, where tryptophan is an amino acid that can actually be converted to melatonin in the body.  Although there is no evidence to support that tryptophan causes sleepiness (I will likely devote a whole post to this when we get closer to Thanksgiving).  Also, as you can see in the figure below, serotonin is the intermediate between tryptophan and melatonin, and, as you can see from the chemical diagrams serotonin is not so different from melatonin, though it does serve different functions (most notably as a neurotransmitter, of which, having too little seems to be a major factor in depression and other psychological disorders).  But, different function aside, I don't know if I would go so far as to say nothing else like melatonin is made anywhere else in the body.

Additionally, its important to consider that we first discovered melatonin in the brains of lab animals.  In order to get melatonin from humans samples would have to be taken from the brains of  human patients who have had to have brain tissue removed, or after they have passed away, or isolated from blood samples.  The Dan Brown book claims that scientists isolated this waxy substance from the pineal from the brains of yogis just after they finished meditating.  If this were true, the scientists would have had to anesthetize the yogis and then perform highly risky and invasive neurosurgery to get to the pineal and extract this substance.  Not only would this have been completely unethical and illegal, but the surgery would either have to have been performed twice on each subject (once before meditating and once after) or on twice as many yogis (half who meditated and half who didn't).  Needless to say, no study like this has been done, and if this mystical substance does refer to melatonin, it is not really waxy, as it dissolves easily in blood, and is refined as a white powder when it is isolated.

So where did Dan Brown get this idea?  My only guess is that there are a couple of studies that suggest meditation can increase the body's production of melatonin, which we assume is coming from the pineal, but could just as easily be the result of the melatonin that is already present in the blood not being broken down by the kidneys (there's no way to know because in studies like these, the melatonin levels are measured in the circulation).  However, given the prevalence of melatonin on the supplement shelves and the number of studies showing that additional melatonin doesn't have any dramatic or convincing healing effects (or even helpful effects with insomnia and other sleeping disorders unless you already have really low levels of melatonin), I would hesitate to call it a "waxlike substance with healing properties".