Thread: food allergies increasing in number and severity

i was watching the nightly news with Brian Williams and they brought up a recent study done on food allergies in children age 18 and under. the previous estimate the US gov't gave for food allergies in the population was only 4% however the study revealed that in this new generation the proportion is approaching 8%.

some may question the government's previous estimate, however i'm more apt to believe that the observed difference is a result of a sampling distribution that resulted in a higher average age for their study. this means that our children are more prone to food allergies than we are.

additionally the recent study showed that children not only have more food allergies but more severe allergies than we do, with 1/3 of those affected showing severe reactions to their allergens.

what could be causing this dramatic increase in allergy severity and prominence in the population?

Call it coincidence if you like, but many of the foods we--and our children--eat contain ingredients from genetically and hormonally modified organisms. The rise in food allergies might have something to do with the proliferation of Frankenfoods.

It's conjecture, but a study comparing allergy prevalence among kids raised on organic, non-GMO based foods vs kids raised on GMO-based foods might produce a revealing result, or two.

If we take as given that we're not just doing a better job at sampling (for example, the prevalence of ADD has risen as more people know about it now and are hence looking for it), then I'd speculate it has to do with the way we are raised.

I propose that young people in the past several years have spent less time outside during adolescence, and their immune systems have not been provided as much opportunity to adjust. In contrast, in the past when we didn't yet have the internet or gaming systems or 500 channels on the television, adolescents spent a considerable amount more time outside and hence their immune systems learned to accommodate more allergens.

This is just a hypothesis based on gut feeling (and the assumption that it's not merely an increased visibility of the sample population). I don't really have any data to back it up.

Originally Posted by starlarvae

Call it coincidence if you like, but many of the foods we--and our children--eat contain ingredients from genetically and hormonally modified organisms. The rise in food allergies might have something to do with the proliferation of Frankenfoods.

It's conjecture, but a study comparing allergy prevalence among kids raised on organic, non-GMO based foods vs kids raised on GMO-based foods might produce a revealing result, or two.

Allergies arise because the body is recognising a protein in the food as harmful, and initiates an immune response against it. Additionally, the mechanism of the immune response to any substance can drastically change the effect on the body, e.g., take hayfever: a predominantly IgG response (IgG binds to the pollen) does not initiate an inflammatory response, generally, there are no symptoms, however, when IgE binds to the pollen, an inflammtory response is initiated (red noses, puffy eyes and sneezing).

Why would the addition of a set of genes, that produce proteins that have never been linked to an immune response in humans, increase allergy prevalence to unrelated foods?
These foods undergo extensive trials, if an allergenic compound was produced, even as a by-product, I imagine it would be detected. You cannot possibly speculate that GMO foods are a problem unless you knew specifically what foods were causing the increased allergy prevalence and severe allergies (and if they were GMO or not). Indeed, I too would be very interested to see the results of your proposed study. I agree that the quality of food is becoming much more 'manufactured'; large increases in food preservatives and enhancers with no idea of the effects of any long-term consumption on the population.

Originally Posted by inow

I propose that young people in the past several years have spent less time outside during adolescence, and their immune systems have not been provided as much opportunity to adjust. In contrast, in the past when we didn't yet have the internet or gaming systems or 500 channels on the television, adolescents spent a considerable amount more time outside and hence their immune systems learned to accommodate more allergens.

I agree with this too, children are (almost literally) wrapped in bubble-wrap. The low exposure to harmful pathogens results in a poor maturation of the immune system, but I'm not sure if the same is true for allergenic substances.

Originally Posted by spoonman

I agree with this too, children are (almost literally) wrapped in bubble-wrap. The low exposure to harmful pathogens results in a poor maturation of the immune system, but I'm not sure if the same is true for allergenic substances.

Actually, it's almost a cliche in immunology:

http://en.wikipedia.org/wiki/Hygiene_hypothesis

Oh ok, thanks, very interesting.

Oh ok, thanks, very interesting.

both hypothesis presented here are plausible. however as a supporter of GMO technologies i'm biased and tend to consider the lack of exposure to pathogens and allergenes a more significant cause. to that i'll add that MSNBC cited that as a possible cause during the article that prompted me to post this topic.

in biotechnology proteins from one species are made in cells of another species via DNA transplants. Food allergies generally arise from a reaction to a protein in the food source. it is logical to believe then that GMO foods would only have a higher instance of causing allergic reactions if they were given a few specific proteins that members of our population have a high instance of allergic reaction to.

i am not aware of the extent of this practice in biotechnology, however i feel i should mention it. novel proteins with amino acid sequences that are partially or entirely designed by humans can have a variety of unintended biological actions. addition of these types of proteins in the food supply could well cause the marked increase in the proportion of humans with allergies.

I disagree with inow's sampling error hypothesis only for the reason that the study showed not only an increase in mild allergic reactions(which may well have been previously overlooked) but also a dramatic increase in severe reactions with potentially life threatening consequences. people with these types of reactions don't tend to overlook them, and if the instance of mild allergic reactions has not increased over the past generation, the instance of these reactions most certainly has.

The hygiene hypothesis is currently the best explanation. The tb vaccine has been linked to lower rates of auto-immune disorders and allergies. And children in developing countries are less likely to develop allergies.

We also should be aware that children in developed countries are exposed to a wider variety of foods, and thus to a wider variety of allergens. Not all foods are equally allergenic.

Originally Posted by starlarvae

Call it coincidence if you like, but many of the foods we--and our children--eat contain ingredients from genetically and hormonally modified organisms. The rise in food allergies might have something to do with the proliferation of Frankenfoods.

Poppycock. This is simple, rhetorical fear-mongering rather than logical discourse. Either cite an evidence-based study or leave the rhetoric for irrational political blogs and forums. There might, indeed, be a connection between allergy and a genetically or hormone-altered organism, but there's absolutely no reason to conclude, as you appear to have, that the act of modifying the genes or altering the hormones of an organism causes food allergies. This could be the case with on organism and not with another. Furthermore, it also doesn't follow that non-genetically altered foods are less likely than their genetically altered counter-parts to cause allergic reactions.

Whenever I see or hear someone use the term "frankenfood" I know I can just about dismiss anything else that person has to say about anything requiring scientific or logical explanation.

The slight (ever so slight) rise in the observance of food allergies mentioned in the OP is consistent with the rises that are found in just about everything related to public health in the last few decades. The anthropological answer is that we are simply better at observing these sorts of trends. Many of the protocols for diagnosis have only come about or have been significantly refined in the last couple decades and, in many cases, the technology has improved to allow for better observance, correlation, and monitoring.

Originally Posted by SkinWalker

The slight (ever so slight) rise in the observance of food allergies mentioned in the OP is consistent with the rises that are found in just about everything related to public health in the last few decades. The anthropological answer is that we are simply better at observing these sorts of trends. Many of the protocols for diagnosis have only come about or have been significantly refined in the last couple decades and, in many cases, the technology has improved to allow for better observance, correlation, and monitoring.

This might play a role, but epidemiological studies seem to show differences in allergy and autoimmune disease rates between developed and developing countries. For something like ADD you might say that better screening could account for higher rates, but I think it's difficult to explain rising rates of serious auto-immune diseases with screening. The increase may be an artifact, or it could be real. There is real research done on the hygiene hypothesis, and it is taken seriously by the medical community.

I agree with you that blaming it on GMOs or mystery chemicals in our food is poppycock.

To be fair, I might not have read the passage I was responding to closely enough. I was assuming increased observance from one generation to the next in the West. But observances in the West versus that of developing countries presents challenges as well. Where the methodologies are sound, the data are more reliable, but methods of observance in the West definitely differ in developed nations versus developing nations if only because of technology, access to health care and so on.

If what is being described is an increased observance in food allergies in developing nations where GMO foods are present versus a smaller observed number in developed nations, this would be an interesting, perhaps unexpected result. But, if what you're saying is that there is more observance of food allergies in the developed nations over developing, I think that should be an outcome expected to a certain degree simply due to the differences in technology, access to health care, and more diverse dietary habits.

If someone can point to a database of food allergies by nation, I have the other necessary data and can produce the statistical analyses that correlate observance to Human Development indices of the United Nations. I don't think the HDR looks at food allergies, though it does measure healthcare access and other human development variables.

I don't think GMOs matter, it is rather the incidence of infectious disease, particularly intestinal parasites, that is likely to be a contributing factor. This is from a review article on recent findings related to the Hygiene Hypothesis.

Uneven distribution
The geographical distribution of allergic and autoimmune diseases is a mirror image of the geographical distribution of various infectious diseases, including HAV, gastrointestinal infections and parasitic infections. There is an overall North–South gradient for immune disorders in North America [14], Europe [2] and also in China [15] with intriguing exceptions such as asthma in South America or T1D and MS in Sardinia. There is also a West–East gradient in Europe: the incidence of T1D in Bulgaria or Romania is lower compared to western Europe, but is increasing fast [16]. This gradient cannot be fully explained by genetic differences. Indeed, the incidence of diabetes is sixfold higher in Finland compared to the adjacent Karelian republic of Russia, although the genetic background is the same [17].
Additionally, migration studies have shown that offspring of immigrants coming from a country with a low incidence acquire the same incidence as the host country, as rapidly as the first generation for T1D [18] and MS [19,20]. This is well illustrated by the increasing frequency of diabetes in families of immigrants from Pakistan to the United Kingdom [21] or the increasing risk of MS in Asian immigrants moving to the United States [22]. The prevalence of systemic lupus erythematosus (SLE) is also much higher in African Americans compared to West Africans [23].
These data do not exclude the importance of genetic factors for those immunological disorders, as assessed by the high concordance of asthma, T1D or IBD in monozygotic twins: for example, the concordance rate for atopic dermatitis among monozygotic twins is high (77%) compared to dizygotic twins (15%) [7]. The difference in some genetic factors according to ethnicity [human leucocyte antigen (HLA) gene difference between Caucasian and Asian, for example] is well documented, but probably plays a minor role in geographical distribution in view of migrant data.

http://www.ncbi.nlm.nih.gov/pmc/arti...8/?tool=pubmed

One thing I have noticed during my own lifetime is food allergies becoming fashionable. By which I mean that parents are now asking doctors if their child has a food allergy, and doctors looking harder at that possibility. I seriously doubt if there is any actual rise in food allergies. Just a rise in food allergy diagnoses. Some of which are probably incorrect.

Originally Posted by skeptic

One thing I have noticed during my own lifetime is food allergies becoming fashionable. By which I mean that parents are now asking doctors if their child has a food allergy, and doctors looking harder at that possibility. I seriously doubt if there is any actual rise in food allergies. Just a rise in food allergy diagnoses. Some of which are probably incorrect.

Well there is strong epidemiological evidence that has been repeated in several countries by several different parties that suggest the increase is an actual increase. Especially, when we take into account serious related diseases, like MS, that can't exactly be missed or over-diagnosed.

It's pretty difficult to rule out the overwhelming epidemiological data on allergy rates from essentially every developed country on Earth.

Also, allergy diagnosis is not like something which you can mistake, either someone has an inflammatory response to the allergen or they don't. Many studies are done only with looking at cases confirmed with IgE responses to the suspected allergen.

I have to apologise for my previous double post... smartphones aren't so smart at times.

Good to see some pro-GMO posts, it has the potential to do great things (e.g, golden rice project http://en.wikipedia.org/wiki/Golden_rice, unfortunately its advancement was/is continually met with opposition).

Originally Posted by skeptic

One thing I have noticed during my own lifetime is food allergies becoming fashionable. By which I mean that parents are now asking doctors if their child has a food allergy, and doctors looking harder at that possibility. I seriously doubt if there is any actual rise in food allergies. Just a rise in food allergy diagnoses. Some of which are probably incorrect.

I think this is a very valid point; in the past, many parents who suspected their child had an allergy to a particular food substance may have simply kept the food from that child until the child was old enough to understand not to eat it themselves. Nowadays, I imagine there is an increase in parents who are so concerned for their child's safety, that at the slightest inclination of an allergy, they spend the money to have their child diagnosed (perhaps confirmed by IgE responses, aforementioned by i_feel_tiredsleepy). Now, where was the data obtained from in the original study (is it from confirmed cases from health services)? How many allergies in the past have evaded the metaphorical radar? Are parents today more aware of the harmful effects of severe allergies (e.g., media - think Dan Brown's Da Vinci Code, didn't a guy die from a peanut allergy?). Additionaly, I'd have to concede the hygeine hypothesis is also very plausible, I think a combination of both the H. hypothesis, and a greater awarness of the severity of allergies, coupled with an increased willingness to ascertain safety of children through medical services (i.e., more confirmed cases on record), could be responsible for the increase.

tired and sleepy

A few decades back, diagnosis was entirely by symptoms. It is really, really easy to make a false diagnosis that way.

skeptic, i have mentioned before that the study showed not only an increse in allergies, but a significant increase in the number of severe reactions. now, your hypothesis on misdiagnosis in the past is plausible for mild to moderate reactions, but severe reactions are highly unlikely to go undiagnosed or be misdiagnosed.

in response to some issues raised earlier. the study was conducted as a random sample of US residents aged 18 and under, developed vs nondeveloped countries is not a factor.

Saul

You need to actually post a reference to the study. Simply stating what it says is insufficient for a science forum. Others in the debate need to assess that study.

I should modify my earlier statement though. I accept the hygience hypothesis is most probably a valid parameter in a wide range of human ills. However, I am pretty much convinced that the prevalence of food allergies, and many other ills, are also strongly influenced by changes in diagnoses. OK. Excess hygience in raising kids may also be a factor.