Thursday, May 7, 2015

Alzheimer's I: No It's NOT Just Because There's More Old People!

Since there has been so much fuss over the correlations in Swanson et al., I thought, why not take the dodgiest-looking of those correlations and look into it a little more closely.  For instance, what about their correlation between glyphosate/GMO increases and the growth of Alzheimer’s, suggesting that one could cause the other?  Surely that’s a no-brainer!  As commentators on pro-GMO blogs have already noted, Alzheimer’s is a disease of old age, older Americans are increasing, so naturally there’s an increase in Alzheimer’s—isn’t there?

But wait.  If a growing number of aged was sole or even main cause, then the increase in numbers of old folk should equal (or not much increase) the increase in the number of Alzheimer’s deaths.  If however there turned out to be a discrepancy, with the second figure substantially higher than the first, then some new factor or factors must be causing that increase.

I took age 65 as the cutoff point, partly because it’s a division found in census data but mainly because 98% of Alzheimer’s deaths occur after 65.  And the conclusions were stunning.  From 2000 to 2010, the over-65s increased by 13.1%.  But in the same period, deaths from Alzheimer’s increased by 39.1!   In other words, Alzheimer’s deaths increased three times as much as would have been predicted by a mere increase in the elderly population.

Clearly, some environmental factor that is both new and widely-distributed must be causing that increase.  But why should glyphosate be blamed?  There are several good reasons.

Of all toxic chemicals, glyphosate is the one whose use has increased most dramatically over the last quarter-century.  GMO advocates often state that the growing of GMO crops has reduced the quantity of pesticide sprayed.  That is a half-truth, and, as in every half-truth, the part that isn’t true is false.  “Pesticide” is a blanket term for herbicides, insecticides and fungicides.  It is true that insecticide use has been reduced.  But that is not true for herbicides.  You can make plants toxic to insects, but you can’t make them toxic to weeds.  All you can do is make them resistant to herbicides and then spray indiscriminately, crops along with the weeds.  And that process eventually produces herbicide-resistant weeds, so you have to spray more.  Not to mention the recently-introduced practice of spraying crops, GMOs and non-GMOs alike, with pesticide (mostly glyphosate) so as to dry them out immediately before harvest.  The lie that GMO crops have reduced pesticide use is repeated ad nauseam on GMO sites, but in fact any reduction in insecticide use is more than offset by the increase in herbicide use.  Here’s the truth:

“Herbicide-resistant crop technology has led to a 239 million kilogram (527 million pound) increase in herbicide use in the United States between 1996 and 2011, while Bt crops have reduced insecticide applications by 56 million kilograms (123 million pounds). Overall, pesticide use increased by an estimated 183 million kgs (404 million pounds), or about 7%.”  Glyphosate is by far the commonest herbicide because it was the first for which crop-resistance was originally engineered.  In the U.S. the use of glyphosate went from 27 million pounds in 1996 to 250 million pounds in 2009.

Of all toxic chemicals, glyphosate is perhaps the most multivectorial.   It can enter the human body via air, water, or food.  Since the vast majority of corn, soy and sugar-beet are now glyphosate-resistant, most processed food will carry residues of glyphosate, which--however infinitesimal each one may be—can accumulate over time in the human body.  It follows that there are very few people in the US who have not ingested glyphosate, a fact that makes epidemiological studies difficult, for the following reason.

The best way to perform an epidemiological study is by dividing populations into two groups: those that have been affected by the presumed pathogen and those that haven’t.  Tobacco was a classic case.  There were people who smoked and people who didn’t.  If tobacco caused lung cancer, you should find significantly more cases in the second group than in the first.  And you could refine the search—those groups that smoked more should have more cancers than those who smoked less, and the same with lifelong smokers versus those who gave it up.  That’s because smoking a cigarette is a conscious, deliberate choice.

But because there are so many vectors and because none of them involves a conscious decision (in the absence of labeling laws, we have no idea whether what we’re eating has been sprayed with glyphosate or not, whatever our attitude towards GMOs), it’s not possible to determine which sections of the population might be affected and which might not.  But what about areas where there’s been spraying against those where there hasn’t?   Surely there should be some difference between these, if glyphosate was involved.  

There are two good reasons why there shouldn’t be.  One, spraying isn’t just farmers in rural areas—it’s golf courses in suburbs, and municipalities in parks, and householders in their own yards.  Two, even if the rural-urban distinction could be made, there’s no reason to believe—contra the facts of tobacco-smoking—that greater exposure to glyphosate would correlate with higher incidence of Alzheimer’s.  Glyphosate is an endocrine-disrupting chemical (EDC), and as I showed in ‘Unsafe at Any Dose?” EDCs can cause damage at doses as small as one part in a billion.  Moreover, an EDC harmful at these levels may be completely harmless at far heavier doses.  The reason’s simple: chemicals can harm you in more ways than one, at more levels than one, and the two different effects can occur at very different dose levels.

That’s why Swanson et al. could deal with the glyphosate/ Alzheimer’s correlation only by taking figures for the whole population.  Which is what leads pro-GMO folk to think that they can explain away the data by repeating their mantra “Correlation is not causation” and drawing phony graphs between rising diseases and any other factor that happens to have gone up in the last couple of decades.  Like this, for example:

“There’s a plethora of items whose prevalence or use has increased during the past 20 years: the number of electronics we own, the number of pedicures women get, the amount of coffee we drink, etc., and each would make an equally convincing graph…” 

So says Layla Katiraee, “a Senior Scientist in Product Development at a biotech company in California”.  A similar-looking graph, sure.  But “equally convincing”?  To “a Senior Scientist”?  I doubt if anyone with an IQ above room temperature would think that something meant to beautify your feet would be as likely a cause of death as something designed to kill living organisms. 

But how could glyphosate hurt us, when its makers assure us that “Glyphosate inhibits an enzyme that is essential to plant growth; this enzyme is not found in humans or other animals, contributing to the low risk to human health.”  That’s another GMO lie, and it’s already the subject of a California lawsuit.  More on this next week, when I’ll write about the only link still missing from our chain of causal evidence connecting glyphosate to Alzheimer’s: exactly what glyphosate can do to humans, and how it can do it.


  1. Come on, are you seriously claiming glyphosate bioaccumulates? It goes against the nature of the compound. Don't be a detox myth believer. Not all toxins accumulate in our system until we drink enough kale juice to flush them out.

    Bioaccumulating compuonds are typically fat soluble. Glyphosate is water soluble. Generally, a substance can't be both. The rapid excretion of glyphosate from the body in urine is a well known fact supported in peer reviewed literature.

    So, I guess I'll have to wait till the next post to get filled in on any actual causal link between glyphosate and Alzheimers. None has been shown in this post despite the claim of a chain being formed. Here's why:

    You claim any intelligent person would think glyphosate is more likely to cause something like autism rather than, say, drinking coffee or getting pedicures because it's toxic to life

    Well, drinking coffee with caffeine subjects us to an array of carcinogens, toxic to life. Caffeine itself is as much a pesticide as glyphosate - it just wasn't engineered into the plant, the plant developed it's ability to produce an insecticidal compound naturally.

    Organic food contains more phytochemicals than normal produce. Many of these compounds that we find to be nutrients have other purposes in the plants - like protection of plants from insects and microbes.

    So, why aren't these compounds that are designed to be toxic to life more or less likely to cause autism or alzheimers?

    You have been defeated by your assumptions on this matter. You seem to have bought into the "IT"S POISON" hyperbole about pesticides without realizing that not everything poisonous to one form of life is poisonous to all forms. And thank god that we can take antibiotics without toxic effects at normal doses.

    But I guess the EDC / nonmonotonic fallback beats all arguments. Nevermind that glyphosate's actual EDC characteristics are not well supported or well accepted, and I don't think there is a single study claiming nonmonotonic effects.

    So at best, you've created a reason to doubt. But your reason to doubt glyphosate's safety would be just as reasonably applied to caffeine, or a host of other bioactive molecules that haven't been EDC tested by a yet to be defined protocol.

    1. If we flushed all poisons out of our bodies completely, nobody would ever be poisoned by anything except stuff like prussic acid or curare which acts too quickly to be flushed out in time. Do you really believe the human body is efficient enough to flush it ALL out? And I don't care how tiny the residue is, when 70% of all foods contains GMOs, that's going to build up over time until it reaches endocrine-disrupting levels.

      No-one's claimed nonmonotomic DCs for glyphosate? You may be right, Has anyone shown it has a monotonic DC? Not that I know of. Are there ANY studies of glyphosate's response curve? I suspect not. Do you think that's outrageous? I do. Do you think we should be left in ignorance? I hope not.

      And no-one's trying to put coffee in 70% of food without even letting us know where or when.

    2. Your describing biaccumulation. And it's not a characteristic of glyphosate. It's pretty poorly absorbed from the gut. What does make it into the blood is pretty much completely excreted.

      Toxic substances can do their damage in the time between ingestion and excretion. They don't need to bioaccumulate to do harm.

      To lend you some help, what you are (or should be) concerned with is a sustained dose from having some of the suspect chemical in the subject's normal diet.

      Are you seriously suggesting that nobody's done normal toxicology studies on glyphosate? I find that grossly ill informed assumption outrageous. How do you think LD50, NOAEL and the like are determined? If you're in ignorance, it's a voluntary ignorance.

    3. Sorry, Mike, you're the one with the voluntary ignorance. I'm perfectly well aware of how NOAEL and LD50 are determined, but I'm also perfectly aware, which you don't seem to be, that in the last few years it's been shown that NMDRCs are extremely common and that present methods of safety determination are completely inadequate. Don't take that from me, take it from the Endocrine Society, and if you know anyone better qualified to weigh in on issues of toxicity, just tell me!

    4. So, why aren't you crusading against ALL of the other potential EDCs? Soy, carrots etc?

      You should be equally outraged that there is no determination of effect for any of the other ones, including natural ones?

      It's context. Just like how we ingest plenty of carcinogens just eating natural mushrooms or drinking coffee. You could never get the same amounts of pesticides from residues that we ingest from normal natural food. So, why panic over chemicals?

      If EDC's are so ubiquitous in all kinds of food and in synthetic chemicals, are we getting more of more powerful EDC's from pesticides than foods? If not, than I'd say that in the context, based on history, we don't have all that much to worry about.

      It's the Dr. Ames argument, and it's a solid one.

      So, where's the outrage over phytoestrogens in natural vegetables? Or you're picking on glyphosate because of a predisposition against genetic modification.

    5. I'll say this for you, Mike. You don't give up easy.

      No I'm not "picking on glyphosate because of a predisposition against genetic modification". I don't have a predisposition against anything--I go by the evidence. Glyphosate is more ubiquitous than any other EDC, carcinogen, or whatever. It's in 70%+ of our food, thanks to herbicide resistance and processed foods. It's that, rather than GMOs per se, that I'm "picking on" (not that GMOs don't have problems of their own). I just resent being poisoned for somebody else's profit.

    6. What is the basis of that claim? Most ubitquitous and present in 70% of food?

      Has that been verified? Growing crops with glyphosate is not a great predictor of finding it in products like soybean oil or HFCS or sugar. If you are basing your claim around the prevalence of ingredients from RR crops, then your estimation is probably severely impaired.

      If you're going by the evidence, then why are you siding with minority reports rather than one-off study results? I'm not saying that consensus = correct, but going strictly by evidence, then the weight of evidence would not point you towards your conclusions.

    7. Because you attach more weight to a report of the presence of any substance than reports of not finding any. There's many reason for saying you found nothing--you weren't looking properly, you were looking in the wrong place, your methodology was at fault, etc. etc. There's only one reason for finding it--it's there! Numbers have nothing to do with it.

      As for the 70% claim, I read in some Monsanto piece that there were GMOs in 70% of our food (given as a reason for thinking they must be safe since no-one had reported sickening) and since the vast majority of GMOs in processed foods are RR, then the statement must be true.

    8. Or they didn't find it and reported that they did. I'd call your analysis a false-dichotomy. It's not a simple either or. A positive result is not unambiguous.

  2. Seperate post on that lawsuit. Why are they suing Monsanto? I read the 1991 report. It is not lacking in justification as the lawsuit claims. They did use some of Monsanto's historical data when evaluating certain pre-cancerous abnormalities. Unless they're claiming that this was faked information, the EPA's panel would be the ones to

    Typical activist nonsense. This lawsuit looks like nothing more than the typical headline grabber. It can't win. It won't win. It was never intended to win. It's a reason to create more doubt.

    "Judgment is sought against Monsanto to prohibit the company from continuing to make the claim that glyphosate targets an enzyme not found in humans..."

    Why would that be judgement sought? It's an absolutely true statement. If there are side effects, then seek judgement against the part of claim that says it doesn't pose any threat to people. Why are they trying to ban the perfectly true part of the statement.

    What does this lend any credibility to? The only thing it does is show that Nancy Swanson is an activist, and willing to promote any idea that hurts her oponents, regardless of voracity.

  3. Why would a desire to consume large quantities of food influence Nancy Swanson one way or the other?

    Actually the claim is true. As you suggest in your second comment, you will have to wait for part II to see why, but because I'm in such a good mood today I'll give you a really good clue.


    1. You got me on the vowel. It only took me 4 days to realize what you meant.

  4. Median time from diagnosis to death from alzheimers is about 8 years. If increases in glyphosate use increased the rate of alzheimers (and this the death rate ~8 years later) then one would expect an approximate 8 year lag period between the adoption of GM crops and a spike in alzheimers deaths.

    Diagnosis generally currently only occurs once dementia has set in, but scientists have been able to detect the signs of alzheimers up to 20 years before the disease is detectable. Even if we give a conservative figure of 2-3 years of non-symptomatic disease presence this would still throw a further wrench into the hypothesis (you have to add 2-3 years to the jump for the correlation to mean anything, whereas in the correlation as shown in the paper there is essentially a direct correlation rather than a time lag correlation)

    The Swanson paper admits that Alzheimers shows a big jump due to coding changes, the paper also shows a leveling off of alzheimer's deaths just as one would expect (given an 8-12 year median onset to death figure) them to be taking off (1996+8 to 12 = 2004-2008 - where the graph in the Swanson paper plateuas)

    There are similar issues with many of the correlations Swanson brings - Parkinsons for instance has a 10 year average survival rate from diagnosis. Swanson paper shows death rate leveling at around 2006 - 2006 bang on 10 years after the introduction of glyphosate resistant crops, so anyone whose parkinsons was caused in 1996 by something, and immediately diagnosed (which seems unlikely given the progressive nature of the disease) would expect, on average, to live to 2006.

    Autism numbers are equally out of whack. It is widely recognized that autism is caused/detectable during early development in utero. So causative factors would have to be minimally at around this time. Swanson data looks at 6-21 year olds enrolled in IDEA - so you have to offset the numbers *minimally* by 6 years (ie autism caused by something in 1996 wouldn't turn up in these numbers until 2002 - so any rise between 1996 and 2002 categorically cannot be attributed to increased glyphosate use due to GM crops.

    Obesity too seems an odd one - people don't just suddenly become obese, obesity takes time, so there should be a significant lag period between a causative agent and onset of obesity, and certainly a significant lag period between causative agent and death from obesity (one has to, I would imagine, be obese for quite some time before it actually kills you (if one were being cynical one might suggest that there is a significant correlation between obesity and many of the diseases covered....

    Diabetes - check
    Pancreatic cancer - check
    Bile duct cancer - check
    Renal pelvis cancer - check
    Bladder cancer - check
    Thyroid cancer - check
    Hypertension - check
    Stroke - check
    Renal disease - check
    Crohn's and UC - check (this one surprised me somewhat, I cannot fathom having active crohns and maintaining weight at all, but then the period priod to going active is what is important...)

    So all these diseases that show a correlation with glyphosate use in general have also been shown, specifically, in epidemiological studies, to correlate to obesity. Obesity clearly takes time to manifest and thus cannot be attributed to glyphosate (according to the CDC obesity rates essentially went haywire in the 80's and subsequently levelled off - one would of course expect a lag period between onset of obesity and diseases related to obesity... which is precisely what one sees (unlike the reported association with glyphosate where the effects are immediate or in the cases illustrated above actually predate the glyphosate use...))

    1. It's like you stole the thoughts out of my head. I'm pretty sure I proposed lack of lag issue in response to Derek's argument that nobody has substantively criticized the swanson line-drawing exercise.

      I have also done the obesity-checklist on other discussion forums. It takes seconds to google the disease + obesity and get numerous hits that link the disease with obesity. Occam's razor applies.

      I have second hand knowledge of seeing how these diseases are linked - not by glyphosate. Obesity causes diabetes, untreated diabetes causes strokes and heart disease and hypertension. Right there, you have to ask about the cause-effect relationship Swanson tried to show. We have a known cause - obesity. I don't think anybody is really prepared to correlate obesity with glyphosate. I hope not at least- the confounding facts on caloric intake and exercise trends would have to be overcome.

      I'm not sure why people are dazzled with R^2 values. They aren't really all that meaningful in the first place.

    2. There's a lot going on here, and I'm halfway through researching it (yes, Ewan, I freely admit my biochemical knowledge started around zero, but surprise surprise, this stuff is learnable) so anything I say here and now is still provisional. What we have to do is ask ourselves why. Why are all these chronic diseases appearing around now? If they're due to obesity, why are people getting obese?

      Mike said, " I don't think anybody is really prepared to correlate obesity with glyphosate." Well, Swanson did (see her Table 13). And I don't know what facts he has in mind about caloric intake and exercise. But did it never occur to you that there might be a single basic cause for why all these diseases of largely unknown origin are growing and spreading?

      I suspect it may lie in the architecture of single cells. I'll start to explore this in a post I'll try to get up in the next couple of days. Think "microtubules". Two days ago I'd never heard of them, so let's see where they lead us.

    3. If one is going to postulate that obesity and glyphosate are related though, then the correlation is the wrong way round, you'd have to take it that obesity caused RR crops rather than the other way around...

      Obesity in the US increased dramatically during the 1980's and essentially plateaued by the early to mid 90's. Any causative agent for obesity then would have to exist in this timeframe, not after it, thus RR crops cannot be implicated in a rise in overweight/obese individuals considering that such a rise plateaued essentially at the same time that RR crops were released (the conspiracy theorist might postulate that RR crops caused a cessation in obesity due to some as yet undescribed endocrine effect)

  5. Not to beat a dead horse, but if obesity was the underylying issue, and it was cascading, we'd just be seeing the results now.

    Derek, you seem to be ignoring the gorilla in the room. The necessary time offsets for CHRONIC diseases is not anywhere in the drawing exercise that Swanson undertook.

    You asked for substantive criticism. This criticism is damning to Swanson.

    You are also ignoring my previous criticism regarding why only certain GMO stats were used on some graphs, and not on others. That is pretty unforgivable. The reader is left to assume that the data is cherry picked to make it look better. In a scientific study, you define the variables you would compare, then compare them and present the results. In a fishing expedition, you look at whatever you think might make sense, then only present evidence that supports your idea, while leaving off any data that would harm your idea.

    Swanson is the latter. Don't be so surprised it is written off by the entire scientific community.