Industrial nations have seen a strange and troubling rise in allergies, asthma and autoimmune diseases, including Celiac disease and Type 1 Diabetes. In this interview, we talk with experts from the University of Chicago Celiac Disease Center and with National Jewish Health Immunlogist Andy Liu in Denver and what they think is going on, and why they think one culprit might be something called “The Hygiene Hypothesis.”
We also explore how the shift to industrial style farming and eating might be increasing our chance of our immune system getting ill, with Agricultural Scientist, Charles Benbrook of The Organic Center.
This interview first broadcast on KGNU Boulder/Denver, as part of a special, week-long look at genetically modified crops, an issue being hotly debated in Boulder, Colorado. Here’s the complete science show. Go here for extended interviews with Charles Benbrook, Andy Liu, Carol Shilson, Stefano Guandalini.
Transcript of THIS 18-minute story is below:
Around the nation,, some communities are battling whether or not to continue planting, and expanding, genetically modified crops. There’s plenty of debate about whether farmers can stay in business if they don’t grow GM crops. If we ban GMOs, do we end up with fewer poisons or more? Can we afford to move away from regular use of both GM crops AND pesticides? Can we afford not to? An how is our increasingly industrial style of farming, and living, affecting the troubling rise of several diseases, including three that begin with the letter A: They are Autoimmune Disease, Allergies and Asthma. To find out more, we go now to a world leader in the study of asthma and allergies in Denver, National Jewish Health. Andy Liu, an immunologist at National Jewish, says allergies and asthma used to be fairly rare, but the percentages of both are now high enough to make them commonplace.
LIU
So allergies would be about 50%. It would be slightly over 50%. Asthma is running around 10 percent.
In the 1960s, only around 10% of Americans had allergies. Asthma? Maybe 3%. That was when researchers starting tracking its rise, and, Liu says they discovered that with each decade, the incidence of allergies and asthma went up around 50%. He says it MIGHT be leveling off some now. But from 1960 through the 1990s, the rate of asthma and allergies went up over three hundred percent. And Liu says this increase is NOT just due to better diagnosis.
LIU
Actually with allergies, you can allergy test, and so you can then look at the studies with allergy tests, and you can see that’s sort of an adjusted number, that 50% per decade.
What he’s saying is that researchers did subtract out the increase in allergies they could attribute to better diagnosis, and the net, adjusted number is an increase of 50% per decade. Increases in prevalence have also happened in autoimmune diseases, such as Type 1 diabetes, rheumatoid arthritis, and a genetically based disease called Celiac.
SHILSON
It is most definitely genetic. It’s the world’s most common genetic autoimmune disease, actually.
That’s Carol Shilson, Executive Director of the Celiac Disease Center at the University of Chicago, which is one of the world’s leading centers for the study of celiac disease. As for what celiac is, well, if you have this condition, eating gluten containing foods, such as wheat or rye, will trigger your immune system to attack your digestive organs. Speaking with us on Skype, Shilson said that celiac is common in most industrial countries, including the U-S and the nations of Europe.
SHILSON
They’re the same, across the U-S and Europe, the prevalence of the disease, which we now know to be 1 percent and leaning toward 2 percent.
In the U-S, celiac diagnoses have been skyrocketing, partly because more doctors are finally becoming aware that it’s important to screen for this serious food intolerance. But, even after subtracting out the effects of more awareness and diagnosis, celiac disease is increasing . . . listen again to Shilson . . .
SHILSON
The prevalence of the disease, which we now know to be 1 percent and leaning toward 2 percent,
What she’s saying here is that not long ago, about 1 in a hundred people tested positive for celiac disease. These days it’s closer to 1 in 50 people. And all that is up from 15 years ago. The Medical Director at the Celiac Disease Center is Dr. Stefano Guandalini. In Europe, where doctors have been more aware of celiac, they used to report that 1 in 250 people had the disease. Now it’s closer to 1 in 50, and Guandalini warns the rates are still rising.
GUANDALINI
There is certainly an increase in true prevalence of this condition which is not unique for Celiac disease it happens for other autoimmune conditions as well as allergic conditions.
But here’s something strange. Celiac is a genetic condition – and genes don’t change a lot in just 50 years. So why is the rate of celiac disease going up? Sharon Shilson agrees that this is a puzzle.
SHILSON
It is! You could do a lot of research on that. Many have, and we still haven’t concluded exactly what is causing it, but it’s definitely trending up.
As for how fast it’s trending upward, here’s Guandalini:
GUANDALINI
Every 20 years it doubles, which is, of course, concerning.
That’s similar to the rate of increase for allergies. But while the increase of allergies, in the U-S, MIGHT be starting to level off, it’s not clear whether the rate of increase in celiac has peaked. So, why is it going up so fast. Some people blame genetically modified crops. But we didn’t have GM crops in the 1960s. And that’s when many of these diseases started trending up. GM crops didn’t make that happen. Now we did have pesticides, and we did have people increasing their consumption of sugar, and lots of mass-produced food items. Guandalini says these might all be part of the equation, but he is more inclined toward another culprit:
GUANDALINI
My understanding is that the most accepted theory which really has some rather strong base in epidemiological observations, is the so-called hygiene hypothesis.
The hygiene hypothesis states that as people move from family farms, to cities, they lose contact with beneficial barnyard microbes. Guandalini says there are also other ways we’ve made our world awfully clean, and all that hygiene has left our immune systems confused about what to attack inside our bodies and what it’s safe to leave alone.
GUANDALINI.
Because we live in a much cleaner society, and because we use vaccines, fortunately, the rates of infection and the rates of diffusion of bacteria has greatly decreased. As a result, especially in the first 18 months of life or so, our gut immune system has not been exposed to the load of antigens coming from the environment that were expected by Mother Nature to be there. In experimental animals if you reduce the exposure of antigens to the developing gut, as a result you have serious complications in terms of the animal immune system developing never actually developing so well and functioning well. And the response to subsequent stimuli is then skewed toward reactions that are either on the allergic or on the autoimmune type.
Back at National Jewish, Immunologist Andy Liu agrees that one change driving our immune-related diseases might be the trend to move away from the small farm model He says our more urban, industrial, hygienic way of living and eating, might might be making us more allergic.
LIU
The hygiene hypothesis may actually have to do with microbes, in particular bacteria, that may be healthful.
Liu says that allergies and asthma are much less common on small farms where people really do live close to their animals.
LIU
Places where people are farming with domestic animals, or living close to their animals. The thinking is, It might have to do with enrichment of your microbial community. By living close to animals like that.
But is the move away from farm animals really the biggest bad guy in the rise of allergies and other immune disorders . . . or could the problem with these diseases be more like that parable regarding the camel?
CAMEL MUSIC FLYING LOTUS
You know the story — Once upon a time, two merchants were loading a camel. with goods for the market. They started with a bale of straw. then one merchant said, “This camel can carry more.” So in THIS story, they loaded the camel with canisters filled with pesticides and GMOs. They loaded on food policies that made it hard for small family farms to stay in business. They added the burden of making whole, natural, local foods cost a lot. They added processed foods and lots of sugar. The camel by now, was shaking. Then the merchant noticed that a single straw had fallen from the BALE of straw. “No sense in wasting even a single piece of straw. he said., and placed it on the camel.
So when it comes to the straw that breaks the camel’s back — or that breaks the immune system of a person , is the hygiene hypothesis the only thing to look at? Or could the increase in immune disorders involve a lot of things relating to moving away from family farms? So, not only fewer barnyard microbes, but also less whole, natural, local food? More pesticides? Plus toxins introduced by GMOs. One of those toxins made headlines last May. The study came from Canada, and it was published in the Journal of Toxicology, about a toxin in BT corn that was never supposed to show up in human blood. But it did, and that’s an issue, according to Charles Benbrook. Benbrook used to head up the National Academies of Science’s Board of Agriculture. Today he’s chief scientist at the Organic Center, a Boulder-based non-profit whose mission is to conduct credible, evidence-based science on the health and environmental benefits of organic food and farming and communicate them to the public. Along the way, they also discuss the dangers of pesticides and GMOs, which leads back to that BT Corn toxin that the Canadian researchers found in people’s blood. Here’s Charles Benbrook:
BENBROOK
They tested the blood of pregnant woman and women who had just had their babies, and they tested umbilical cord blood to see if they could detect any sign of genetically engineered crops, and to everyone’s amazement that follows this area of science, they detected the Bt corn protein in 70% of the samples. Not just in the women’s blood but in the umbilical cord blood.
Bt Corn is . . .
BENBROOK
Bt, bacteria thuringiensis Bt is corn that has been genetically engineered to express a natural toxin throughout the plant so that the corn ear worm chews on the plant, it ingests enough of the Bt to kill the ear worm.
Chuck Benbrook, is this a protein like in meat, or milk or soy or chicken that the body readily digests for energy and building blocks, or it this a toxin?
BENBROOK
It’s a toxin to the insect because it binds to the stomach wall and basically eats a hole in it. The insects die of dehydration because it loses its body fluids. Does not have the same effect on a human being’s stomach. The reason this finding is so significant is that for 15 years since Bt corn has been planted, the conventional wisdom and the contention by the biotech industry is that — note that with corn, there’s Bt corn chips, and Bt sweet corn, if you eat corn in any form, you are ingesting these toxins because they’re in the kernel. But the industry submitted data to the regulatory agencies around the world that the protein broke down in seconds because of the ph of the human stomach. And therefor, regulators didn’t do any risk assessment on it.
I don’t think 70% of this protein in the blood of women and children . . .
BENBROOK
That’s why I’m highlighting this particular study as the kind of big surprise that isn’t supposed to happen with a technology that many of its advocates have said is the most carefully tested food technology ever, when in fact there’s been very little independent science on how they affect the nutritional quality of food, whether there are novel toxins produced, and how these GE compounds move through the human digestive system.
While it’s disquieting to hear that we may have these proteins inside of us, This is not the mainstream hypothesis for what’s causing autoimmune diseases, autism, allergies and asthma, where the rates have been going up, the main medical hypothesis is that it’s just too clean. If I were to ask most experts on allergies and immune problems, that’s what they would point to. Quite honestly when I’ve checked with them, they’ve been pretty dismissive that GMOs could play any part.
BENBROOK
GMOs may not play a huge part. But, the pesticides that are used in conjunction with GMOs may be playing a significant part that people realize. What the new science is showing is that there appears to be some common causes for ADHD, asthma, allergies, excema, several autoimmune disorders that can afflict certain kids and once they get one, they often have trouble with others.
This is troubling because right now, the rates of increase in the United States and in other developed nations are a doubling of these diseases every 20 years such as for celiac.
BENBROOK
Something is causing this, and I think the evidence is pointing to exposures, during pregnancy, to so-called endocrine disrupting chemicals that have the capacity to trigger what’s called an epigenetic change. We now have strong evidence that some common pesticides that the average American is ingesting two or three or four residues a day, in their daily diet, can be a risk factor for obesity, for diabetes, for certain forms of cancer, for autism and for a variety of neurological diseases. So this is really incredible that very low levels of exposure during fetal development can wreak so much havoc in a developing child.
We’re talking about a theory here. We can’t guarantee this is something that is driving these epidemics.
BENBROOK
We’re never going to be able to prove what caused a given child to have autism or a birth defect, or why one person in a family that smokes gets lung cancer and another person in the same family doesn’t. But the impact of prenatal, fetal development exposures, so-called epigenetic changes, has been demonstrated in multiple studies with laboratory animals, and there’s no reason we shouldn’t expect these to be occurring in the human population.
So all this is possible. Right now, we know that China is developing GMOs at an amazing rate. Their expectation is that’s what is needed for production of food. We know if we don’t have GMOs, we still have pesticides. How do we get around this? What can we do?
BENBROOK
The future for agriculture is integrative approaches where you manage the farming system to sustain fertile and healthy soils and healthy plants and animals and you maintain enough biodiversity so that very few pests build up to levels to threaten a crop or livestock. There are millions of farmers around the world doing this. They’re not dependent on GM seeds. They don’t use many pesticides. When they do have to use a pesticide it’s usually not as toxic as what farmers in the U-S use, where they have become dependent on these broadly used pesticides. If you choose to control pests with chemicals, the pests will adapt and it will take more and more chemicals. That’s the slippery slope that American agriculture is having a hard time getting off of, and it’s also a slippery slope that today’s genetically engineered crops are pushing the foot down on the gas pedal.
Do you really think that old fashioned farming can compete with all this biotechnology?
BENBROOK
Old fashioned farming with modern equipment and modern genetics and modern science. Absolutely.
That was the Organic Center’s chief scientist, Charles Benbrook, describing how GMO foods might be affecting our health. But whether it’s toxins in GMOs, or pesticides on crops, or the move away from all those barnyard bugs, all these researchers, including Andy Liu from National Jewish and Stefano Guandalini from the Celiac Research Center, they all agree that there’s something about the small farm model, where people lived closer to nature, that seems to have been healthier for our immune systems. And if we can somehow recreate that health, whether it’s through new vaccines, or new probiotics, or perhaps by changing our ways of living . . . perhaps we can take these rising rates of immune related disorders, and bring them down. For The KGNU Science Show, How on Earth, I’m Shelley Schlender.
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