"It ain't what you don't know that gets you into trouble. It's what you know for sure that just ain't so." - Mark TwainA few years ago I read an article--I don't remember where--explaining the paradox that although Monosodium Glutamate is a "universal" flavor enhancer, it is also, unfortunately, a poison, toxic in large quantities. Some people had a higher tolerance than others, the article explained, but there was no scientifically established safe limit.
I accepted this idea, and kept it in mind as I shopped, along with other ideas like the need to eat foods with high nutritional content and treat foods with low nutritional content as a waste of money. But, knowing that it was only a mild toxin (in much the same way as we might view, for instance, alcohol or lactose), I didn't worry too much if I occasionally ate junk food containing MSG.
But this weekend I was reading numerous articles linked to by one master list, "Slightly More Than 100 Fantastic Pieces of Journalism", an list that I discovered through another website I'd never heard of before Friday, metafilter.com, a site which popped up on Slashdot's radar in a post about how Google permanently and suddenly cut off 40% of traffic to Metafilter on November 17, 2012, for reasons that Google hasn't disclosed, which so far has led to 3 staff members being laid off at Metafilter.
Anyway, so I came upon an article that upended my established knowledge about MSG: "The Notorious MSG’s Unlikely Formula For Success", which started by crushing the "mild poison" idea:
Glutamic acid is one of 20 amino acids that are crucial to the human body’s proper functioning. Without it, we would die, but it is referred to as a nonessential amino acid because our bodies can produce all we need on their own, and we don’t depend on consuming it directly with our food. Glutamic acid is found throughout our bodies, where it is crucial to cell metabolism. In the brain, it is an important neurotransmitter, regulating learning and memory. Every second in our heads, quadrillions of microscopic glutamate bombs explode every time a neuron fires, passing electrical signals through our synapses.Huh. So that's glutamate. Far from being a poison, it's actually one of many fundamental building blocks in the human body. The minority component in MSG, sodium, simply makes MSG into a salt and one would expect, without evidence to the contrary, that its effect on the body would be similar to ordinary table salt.
The article went on to explain the history of the paranoia around MSG and how the general public came to be distrustful about it based on articles that were either pseudoscientific (not employing proper methods such as double-blind testing and placebos) or properly scientific but not relevant to the issue of food safety (injecting extremely high doses of MSG directly into the bloodstream of baby mice: this adversely affected neurotransmitter levels in the mice, but would probably not affect adult humans by anywhere near the same extent, due to the blood-brain barrier, and it's common knowledge that injecting stuff into your veins isn't the same as eating it anyway.)
After reading this new article about MSG, I Googled "effects of msg" and found a list topped with anti-MSG articles. These articles generally admitted that yes, glutamate is normal in the body, but it's still bad, citing studies such as the one about baby mice. The #1 search result called MSG a "silent killer", saying:
One of the best overviews of the very real dangers of MSG comes from Dr. Russell Blaylock, a board-certified neurosurgeon and author of “Excitotoxins: The Taste that Kills.” In it he explains that MSG is an excitotoxin, which means it overexcites your cells to the point of damage or death, causing brain damage to varying degrees -- and potentially even triggering or worsening learning disabilities, Alzheimer’s disease, Parkinson’s disease, Lou Gehrig’s disease and more.Wikipedia's entry on Russel Blaylock states,
Blaylock has endorsed views inconsistent with the scientific consensus, including that food additives such as aspartame and monosodium glutamate (MSG) are excitotoxic in normal doses and that the H1N1 influenza (swine flu) vaccine carries more risk than swine flu itself.And yet Mr. Blaylock earned respect in his career as a skilled neurosurgeon. This reminds me of a strange phenomenon that happens occasionally in which highly-respected scientists (not that a neurosurgeon is necessarily a scientist) lose their objectivity and become the staunchest advocates of views that have little or no science to back them up. Such scientists can amass large numbers of followers very quickly. Since most people are unfamiliar with the fine details of science itself (indeed, with science being so specialized, scientists in one field often have to exercise some faith that scientists in other fields are doing "good and proper" science), they put their faith in scientists of good reputation and hope for the best. Consequently, a single popular scientist that promotes an incorrect view can do a lot of damage. At first, followers of the incorrect view include many other scientists as well as members of the media and general public. Eventually, various scientists do enough research to debunk the incorrect view and establish a new, corrected consensus; but the general public tends to lag far behind, still believing what they were first told 10, 20, or 40 years ago--partly out of inertia, and partly because anyone who profits from the old views steadfastly continues to promote them.
The most remarkable example of this phenomenon is Linus Pauling, whose rise and fall is explained (and perhaps sensationalized) in the fascinating article "The Vitamin Myth: Why We Think We Need Supplements":
On October 10, 2011, researchers from the University of Minnesota found that women who took supplemental multivitamins died at rates higher than those who didn't. Two days later, researchers from the Cleveland Clinic found that men who took vitamin E had an increased risk of prostate cancer. "It's been a tough week for vitamins," said Carrie Gann of ABC News.In the end, I don't think this new knowledge about MSG, my new confidence in its safety, will affect my eating habits significantly. The fact remains that many of the products that contain a lot of MSG were junk foods anyway; avoiding those was a good idea before, and it's still a good idea now.
These findings weren't new. Seven previous studies had already shown that vitamins increased the risk of cancer and heart disease and shortened lives. Still, in 2012, more than half of all Americans took some form of vitamin supplements. What few people realize, however, is that their fascination with vitamins can be traced back to one man. A man who was so spectacularly right that he won two Nobel Prizes and so spectacularly wrong that he was arguably the world's greatest quack.
Thus, it turns out, the "100 Fantastic Pieces of Journalism" includes some other pieces that are more weighty and important in the scheme of things. Like the epidemic of invasive species, like crazy ants, which infest houses, destroy electronics, crawl on everything and die in heaps of millions; jellyfish, which are gaining prominence due to the unexpectedly high rate of global ocean acidification; the sickening modern slave trave in Sudan; the plight of the elephants; or the U.S. Predator drone, which strikes fear into civilians in Pakistan and leaves many of its deadly human operators with PTSD.
But the MSG issue is a good example of an issue where people can vehemently disagree even though there is very little opinion involved: whether the effects of MSG are good or bad or neutral, those effects are a matter of fact, and our level of knowledge about it (neither poor nor especially detailed) is also a matter of fact, yet here we have different people making wildly different claims about what the truth is. I wish that the saying were true:
"Everyone is entitled to his own opinion, but not to his own facts."Now if someone profits monetarily from promoting a false belief, that's pretty easy to understand.
"It is difficult to get a man to understand something, when his salary depends on his not understanding it." - Upton SinclairYet those still promoting the idea of MSG-as-a-toxin typically don't profit from it. So what's the deal? Are they just parroting what they've heard before? Perhaps in part, but as this article explains, there is more to it than that.