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Medical Peanut allergy -- What substance causes the reaction?

  1. May 23, 2016 #1

    wolram

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    What is in pea nuts that causes such violent illness and even death?
     
  2. jcsd
  3. May 23, 2016 #2

    ProfuselyQuarky

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    Allergies and other autoimmune disorders occur when the immune system negatively reacts to a something that normally would cause any harm (e.g. peanuts). You can't inherit a specific allergy, but people whose parent(s) had allergies are more likely to get them themselves. Unfortunately, no one knows for sure what exactly causes allergic reactions, aside from knowing that it is caused by, for lack of a better word, misbehaving immune systems. Anaphylaxis, itchiness, and other things associated with allergies, including peanuts, are just symptoms as the immune system fights back unnecessarily. The severity of the symptoms just varies with the exposure and seriousness of each person's allergy. Peanut allergies aren't any more serious than other allergens. It is payed more attention to probably just because it is airborne and many children have it--thus, schools and the entire student body have to be more cautious when dealing with food.

    http://well.blogs.nytimes.com/2014/02/03/as-peanut-allergies-rise-trying-to-determine-a-cause/?_r=0 [Broken]
    http://www.webmd.com/allergies/guide/chronic-allergies-causes?page=1
     
    Last edited by a moderator: May 7, 2017
  4. May 23, 2016 #3

    ProfuselyQuarky

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    Adding to the above (sorry, I can’t edit the top post anymore…idkw) there is no actual “substance” in things that causes allergies. There are very rare occurrences where people are diagnosed with aquagenic urticaria, which is literally an allergy to water. Some are allergic to pure elements like nickel. There are obviously no additional chemicals within these things, but people’s bodies still react negatively to them. Why? It’s a mystery for now (wait ‘till I research it in college and then I’ll give you the answer, wolram). But, oh, how dreadful allergies are....
     
    Last edited: May 23, 2016
  5. May 23, 2016 #4

    TeethWhitener

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    While this might be true in some cases (of which I'm not particularly aware), food allergies are generally caused by some protein (or other component) in the food that binds to an antibody produced by the body's immune system (usually IgE) that triggers an inflammatory response. The most well-known pathway in this response involves histamine (which is why antihistamines such as Benadryl are used as allergy medicine), but the entire allergic response is extremely complex and involved.
     
  6. May 23, 2016 #5

    TeethWhitener

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    This is not a true allergic response per se. Our bodies are ~60% water, so a true water allergy would probably be immediately fatal.
     
  7. May 23, 2016 #6

    ProfuselyQuarky

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    Just because it is rare doesn't necessarily mean that it is not "real". Though, you're right--I was generalizing and trying to make everything simple. Aquagenic urticaria is not a histamine-releasing reaction.
     
  8. May 23, 2016 #7

    ProfuselyQuarky

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    There are numerous examples...how else can people be allergic to things such as nickel or chromium?
     
  9. May 23, 2016 #8

    TeethWhitener

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    I didn't say it wasn't real. I said it wasn't a true allergic response. Although, I'm not sure if its mechanism of action is known. In at least two cases, it was treated with an antihistamine. Regardless, the point I was trying to make in my first post is that allergies are specific immune responses caused by antibodies binding to allergens.
     
  10. May 23, 2016 #9

    TeethWhitener

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    Chromium and nickel ions dissolve into the skin and are recognized by the immune system: https://en.wikipedia.org/wiki/Nickel_allergy
     
  11. May 23, 2016 #10

    ProfuselyQuarky

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    Yes, I'm aware of that. That was just my response to whether there were allergies not having to do with proteins.
     
  12. May 23, 2016 #11

    TeethWhitener

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    Ok I'm confused. I was responding to your assertion that
     
  13. May 23, 2016 #12

    ProfuselyQuarky

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    I'm becoming confused, as well. Because although you were responding to my assertion that
    Your complete sentence stated
    suggesting that "food allergies being generally caused by some protein" was justification that the statement "no actual “substance” in things that causes allergies" was somewhat erroneous. However, in my statement, I was referring to all types of allergies and not just food allergies.

    Sorry for the confusion. I should have worded my posts better.
     
  14. May 23, 2016 #13

    TeethWhitener

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    Just to clarify, it's true that there's no single substance that causes allergies. And it's unclear why certain people are allergic to certain substances (from a genetic point of view). However, the allergic response itself is pretty well understood, and it occurs upon binding of an antibody to an allergen (which is almost always a protein). Non-protein allergies (like nickel allergies) generally involve the allergen (like Ni2+) binding a protein and causing it to misfold or change its conformation in some other way. Subsequently, the misfolded protein (called an epitope) is bound by the antibody, inducing an allergic response. (side note--I use the term "misfolded" very loosely here.)
     
  15. May 23, 2016 #14

    ProfuselyQuarky

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    I appreciate the clarification, TeethWhitener, since wolram was asking about the cause in the OP. Thank you.
     
  16. May 23, 2016 #15

    jim mcnamara

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    http://www.medscape.com/viewarticle/777380_3 Table 1 has a list of 11 water soluble glycoproteins and proteins that have been found to cause peanut allergic responses. These molecules are unaffected by normal cooking temperatures. So cooking does not *denature them. There may be others.

    Proteins are not commonly named except in the context of a biological pathway. Some proteins with names like casein are made of several different molecules The researchers in the field named them Ara n where n is 1 - 11. Arachis is the genus name for peanuts - Arachis hypogaea.

    Also note - the above is the immediate cause - the metabolic pathway for allergensis (absolute root cause) has apparently many possible causes: heredity and environment interactions. So like a lot of food related medical problems the prevention relies on avoiding something: in this case peanut products in food.

    *denature: "destroy the characteristic properties of (a protein or other biological macromolecule) by heat, acidity, or other effects that disrupt its molecular conformation." - wikitionary Example: cooking egg white - goes from clear and water soluble to "rubbery and white".
     
  17. May 23, 2016 #16

    TeethWhitener

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    Any time :smile:
     
  18. May 25, 2016 #17

    Jonathan Scott

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    Some years ago I heard a theory that the original cause of peanut allergy was that peanut products are very frequently contaminated with very slight traces of aflatoxins, which are very nasty, and that this primes the immune system to react strongly to peanut-related proteins in general on subsequent exposure. I don't know whether this is still considered a viable explanation.
     
  19. May 25, 2016 #18
    There will almost always be something around and in food that our immune system may not like. It is important is to minimize an over reaction from our immune system to these "things". Our immune system will over react if the signals from that "thing" your immune system does not like is amplified. Unfortunately, people in the developed countries are all exposed to metals (aluminum, mercury, etc) so we have those in our bodies and these metals will amplify that "thing". So then our immune systems will over react. Flush away these heavy metals from our bodies and we can minimize allergies and auto-immune diseases.
     
  20. May 25, 2016 #19

    jim mcnamara

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    @st mess - Please provide a peer reviewed citation for your comment about exposure to metals and allergenesis. I would like to learn more if what you said holds water. Thanks.
     
  21. May 25, 2016 #20

    ProfuselyQuarky

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    I'd like to know more about that, too. His statement suggests that the allergies people have/acquire vary and are somewhat dependent on both geographic and demographic factors...I never heard about that before and would love to know.
     
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