Can allergies prevent tumors?
February 7th, 2011
12:01 AM ET

Can allergies prevent tumors?

Whether it's sneezes or hives or a potentially fatal closing of the throat, allergies generally don't bring positive effects.

But some research indicates that having allergies carries at least one health benefit: More than dozen small studies have suggested that people with allergies are less likely to develop gliomas, which are tumors that begin in the brain or spine, and are the most common type of brain tumor.

A new study in the journal Cancer Epidemiology, Biomarkers & Prevention adds to that research, finding that the more allergies a person has, the lower the risk of developing one of these tumors. Many other studies looking at allergy and glioma, although not all, have picked up on this association.

But, like previous experiments on the topic, this new study shows only an correlation between allergies and low glioma risk. It does not prove that this is a direct causal connection, said Bridget McCarthy, co-author of the new report and researcher at the University of Illinois, Chicago.

How allergies would prevent tumors is entirely unknown. Some scientists speculate that the immune system of people with allergies is hyperactive, and therefore guards against gliomas. Dr. Melissa Bondy of the University of Texas M.D. Anderson Cancer Center, who was not involved in this particular study but has done similar research, thinks there is a trigger of the production of histamine - an inflammation-causing compound released in allergic reactions - that protects against gliomas and perhaps even other kinds of cancers.

McCarthy and colleagues took information from 419 patients who had glioma and 612 who didn't who had been to hospitals in NorthShore University HealthSystem and Duke University Health System.  All participants self-reported their allergies - including to pets, food, pollen, medication, and other triggers - and antihistamine use.

According to this new study, there were gliomas among people who reported having allergies.  However, the use of antihistamine did not appear to significantly influence glioma risk on the whole, the researchers found.

But when Bondy looked antihistamine use in her study, she found it actually increased a person's chance of developing a glioma.  She theorizes that certain medications may ease sneezes at the expense of taking away the protective value of the allergic reaction against cancer - but this is also speculation, she said.

An important limitation of this new study is that participants may have misremembered their allergy medication usage and the number of allergies that they have.  And environmental or other factors relating to allergies were not controlled for, meaning that it could be that it's not the allergies but something else in the participants' lifestyle or living situation that accounts for the reduced glioma risk, which is something  the authors acknowledge.

But given that so many other investigations into the topic find a protective effect of allergies against glioma, Bondy said it's likely that there is something going on involving histamines.

To further explore these ideas, Bondy and colleagues are now recruiting 6,000 cases and 6,000 controls for a large-scale epidemiological study on protective factors in glioma.

Bottom line: Don't stop taking antihistamines or try to make your eyes red and watery on the basis of this work.  Much more research needs to be done before any recommendation can be made.

soundoff (61 Responses)
  1. Joe in Colorado

    I like how the article calls these her ideas. I've long written all over the web that it's my belief that a) people who have overactive immune systems are more resistant to cancer– it runs in my family, both rampant allergies and zero cancers; b) that allergy medication likely increases the chances for developing cancers; any time you're supressing an immune response (even localized), there is a probability for greater chance of problems... look at warnings for Elidel, for instance.

    I give the researcher credit for actually getting off her butt and doing the work, but the ideas are far from original. Sometimes I wonder if people read my comments and then take the ideas and run with them– which is fine, but at least give some credit where its due.

    February 7, 2011 at 03:53 | Report abuse | Reply
    • HypMama

      Well, I invented the Swiffer, in my brain, but I ain't a-tootin' my own horn. I also dreamt, once, of iPods after a particularly touching episode of Quantum Leap... No, wait... Ziggy WAS the ipod... just more colorful and bulky, so I guess it wasn't my idea.... (JK)
      There are hardly any original ideas... but, like you said, someone had the knowhow to actually research it. It's funny that you are trying to steal the researcher's thunder, though.

      February 7, 2011 at 04:01 | Report abuse |
    • R Burns

      I, too, am from a family with autoimmune disease and rampant allergies – and zero cancers! My related comments have been left on many websites including medical journals, but I'm not narrow enough to believe I'm the one responsible for stirring the medical field to action. Maybe one voice among many that signals a need for study. At any rate, I certainly do agree that there must be a direct relationship between a body tilting at windmills to fight off enemies that aren't there (pollens and such) and the low incidence of a real enemy, cancer. Or maybe the body realizes there is clinically undetectable cancer and launches an all-out war that we recognize as allergies. Which comes first, the chicken or the egg? And however it happens, I sure hope we find the answer!

      February 7, 2011 at 05:02 | Report abuse |
    • Wzrd1

      It's interesting to notice a decrease in cancer coinciding with allergies. It's bizarre that it's regarding glioma though.
      The brain is an immune privileged area. As such, it is separated and protected from the immune system, to the point of literally having its own immune system.
      That said, some research appears to be showing that histamine can cause the blood brain barrier to "leak" and permit some proteins through. With infections, this can be disastrous, but with a glial tumor, perhaps there is a tag on the cell that the primary immune system recognizes and that triggers either the main immune system to respond OR the brain's defenses.
      Either way, it shows the need for more research.

      February 7, 2011 at 08:51 | Report abuse |
    • MM

      Is it just me or is her english really, really horrible? An example: "this new study shows only an correlation between allergies and low glioma risk" It should be " only a correlation". You do not use the word AN in front of a word that has a consonant as a start.....

      February 7, 2011 at 09:21 | Report abuse |
    • Rick

      I'm not sure a family, even an extended family of 50 or more people, is a large enough of a sample size to prove anything... and since other genes are also shared, it's hard to tell if it's the family's allergy gene or the family's shape-of-their-nose gene (or just coincidence) that no one in the family had cancer... without researchers to set up experiments to increase the validity of the results, anecdotal family evidence becomes no more than an old wives' tale.

      February 7, 2011 at 09:23 | Report abuse |
    • no one in particular

      you must really like to hear yourself talk. it's quite presumptious for you to take any credit for this just because you posted your "ideas" on the web, which has barely been around for even 20 years in any meaningful form. what's YOUR scientific basis for anything besides casual observation and assumption?

      February 7, 2011 at 12:47 | Report abuse |
    • Michelle

      Oh, you should definitely pursue this "Joe in Colorado". That is, if they have a legal system in the world in which you live.

      February 7, 2011 at 23:49 | Report abuse |
  2. DreamerGina

    I call this one of the stupidest things Ive ever heard of. This is more like a guess than anything.

    February 7, 2011 at 04:04 | Report abuse | Reply
    • R Burns

      Dear dreamer, your sleep must be peaceful! If you and your family don't have allergies, count your blessings. And I'd be careful to get that cancer screening. . .

      February 7, 2011 at 05:05 | Report abuse |
    • Somebody

      If you think this is stupid, then you must have not made it past the 8th grade.

      February 7, 2011 at 09:18 | Report abuse |
    • Donna

      It is not stupid. It is called SCIENCE. You observe something, make a hypothesis and then test it. They are going to do a larger followup study and it will be interesting to see what the results are of that. I personally have a lot of allergies but cancer unfortunately runs in my family. Not glioma though.

      February 7, 2011 at 13:45 | Report abuse |
  3. MikeP

    Even when there is a causal link between things that correlate (which correlation itself doesn't demonstrate!) the link can be easily misjudged. Consider the link between life-long health care costs and things like smoking and obesity – those things increase your short term health care costs, but *reduce* your long-term costs. Why? Because more is spent on health care for old age related chronic conditions than for most other things during your life, and both smoking and obesity reduce your chances of being alive long enough to incur those costs. So... the correlation doesn't necessarily demonstrate a protective relationship.

    February 7, 2011 at 05:42 | Report abuse | Reply
    • Unga Khan

      No, both obesity & smoking cause a slow, painful death with many extremely expensive complications such as cancer, heart disease, COPD, liver failure, or renal failure. If you'd like to die young, abuse intravenous drugs or get involved in crime. Also, the correlation between the biological conditions of allergy and cancer isn't the same as the correlation between the socioeconomic variable of healthcare costs and an abstract "overall health".

      February 7, 2011 at 06:50 | Report abuse |
    • Donna

      Unga-heart disease is not always slow and painful. Some people die on their first heart attack with no previous symptoms. I am not sure what percentage that would be of the total. You have to figure lung cancer is very expensive to treat though.

      February 7, 2011 at 13:47 | Report abuse |
  4. BrandonC

    Interesting how the body works. Perhaps all the medication that we take is suppressing the bodies ability to take care of itself. Allergies suck, but instead of masking them with antihistamines/etc, a more natural remedy may end up being safer.
    On a side note, this reminds me of an article I read about how living with a mild starvation state wards off illness as our body compensates by boosting the immune system.

    February 7, 2011 at 07:09 | Report abuse | Reply
    • kbh_12

      There's a lot of truth to this. The main reason is that most of the foods we eat (espeically in a western diet) fuel not just our healthy cells but they fuel the unhealty cells too. By remaining in a state where you're almost always hungry, your weaker "unhealthy" cells cannot strive and are more likely to die off.

      February 7, 2011 at 13:47 | Report abuse |
  5. Greg Wolf

    Do you think the scanners are responsable for the cancer epidemic among TSA workers

    February 7, 2011 at 08:14 | Report abuse | Reply
  6. Kevin

    I think there is going to be more and more things out there in our lives that cause cancer. It's just that it is beingkept quiet for the sake of the almighty dollar for big corporations.

    February 7, 2011 at 08:20 | Report abuse | Reply
  7. Mommabear

    People with Sickle Cell don't get malaria.

    February 7, 2011 at 08:31 | Report abuse | Reply
    • Somebody

      Yea, I learned about that in school.

      February 7, 2011 at 09:17 | Report abuse |
  8. I've got allergies out the wazoo

    "Misremembered?" PULEEZE. The word you're searching for is "forgottten."

    Having said that, this is great news. My Mom died of a glioma and she had no allergies that I know of. However, I'm practically allergic to living, with an overactive immune system. Makes sense actually - with allergies the body would attack an unknown substance like the beginning of a glioma and destroy it before it goes anywhere. Very interesting study.

    February 7, 2011 at 08:46 | Report abuse | Reply
    • Somebody

      I think with the immune system being hyperactive and all it would find something like that faster than someone with a normal working immune system.

      February 7, 2011 at 09:22 | Report abuse |
  9. JM

    I know it's just a correlation and it's new and blah blah blah, but I have to say that as someone with severe allergies and asthma, I was a little happy reading this. Maybe all the watery eyes, sinus infections, bronchitis, stuffy noses etc. weren't for nothing, Maybe there's a silver lining about always being "the sick one." I'm thrilled to learn more about this, however, my father, a long term allergy sufferer passed away from pancreatic cancer in his late 40's... so..... who knows

    February 7, 2011 at 08:49 | Report abuse | Reply
    • Donna

      It appeared that the study was limited to gliomas.

      February 7, 2011 at 13:49 | Report abuse |
  10. Chris

    My dad has allergies and a glioma.... Is he just cursed? Keep studying and find us some treatments and or cures.

    February 7, 2011 at 08:55 | Report abuse | Reply
  11. Reality

    Great. First I have to suffer with these darned allergies all spring, summer and fall, and now there will be one less thing to put me out of my misery.

    February 7, 2011 at 09:01 | Report abuse | Reply
  12. rk

    I have wondered if an allergy might confer some protective benefit, if an allergen is similar enough in structure to a pathogenic antigen – could there be cross-reactivity between different classes of antibodies? An interesting field of study.

    February 7, 2011 at 09:06 | Report abuse | Reply
  13. fireybuddha

    the headline should have read "gliomas," not "tumors." a glioma is a pretty specific type of tumor, and thus the headline was VERY misleading.

    February 7, 2011 at 09:42 | Report abuse | Reply
    • Donna

      A lot of people may not know what a glioma is though. This way they click on the article and learn something.

      February 7, 2011 at 13:51 | Report abuse |
    • BrandonC

      I thought about this too but it may have just been the focus in this particular study. Not to say I believe it, but a lot of times the findings can reproduce themselves in different studies, in this case more kinds of cancer.

      February 8, 2011 at 01:14 | Report abuse |
  14. Chetan

    May be one more reason not to stuff your body with chemical (medications). Handkerchief is just fine. Thanks for article.

    February 7, 2011 at 10:03 | Report abuse | Reply
    • Justamom

      I had the same thought, initially, but then I remembered that my mom has developed asthma over the last few years. Her doctor said it's because her allergies went untreated for a long time. Definitely an interesting study, though–as an allergy sufferer, I'd like to think there's some silver lining, lol!

      February 7, 2011 at 10:46 | Report abuse |
    • justxsayxno

      "Her doctor said it's because her allergies went untreated"

      Just the kind of response one would expect from a drug pusher!

      February 7, 2011 at 11:35 | Report abuse |
  15. justxsayxno

    Some parasites cause allergies and are also known to cause cancer. The same is true of many environmental toxins. If avoidance is not an option then it would be beneficial to have a strong immune system to contend with these. Chronic consumption of antihistamines seems like a bad idea to me. But everything in life is a trade off. Personally I do not put much faith in drug pushers.

    February 7, 2011 at 11:32 | Report abuse | Reply
  16. Jeramiah

    I have hay fever and have a heck of a time during the summer months due to allergies. And I got a brain tumor once. I never believe these articles when they come out every so often. Looks like there was good reason to.

    February 7, 2011 at 11:36 | Report abuse | Reply
    • Donna

      You understand that there is a difference between one person and studying thousands of people, correct? Most correlations are not 100%.

      February 7, 2011 at 13:53 | Report abuse |
  17. Caolan Finegan

    SNEEZING!!! that's the answer 🙂

    February 7, 2011 at 11:45 | Report abuse | Reply
    • BooBoo

      How about sneezing, headaches, lethargy, dizziness, sinus infections and red, teary eyes? That's how I feel every Spring, Summer and Fall. I love winter! More snow and ice please....

      February 7, 2011 at 11:48 | Report abuse |
    • OvernOut

      To BooBoo: Winter is now my favorite season, I am a happy person from Thanksgiving to Easter. If I could move to the UP, I would do so. I also hate air conditioning, it is bad for allergies, too much mold. I do not have it in my house, we would only need it a couple of days per year, anyway in SE Michigan. Think Snow!

      February 7, 2011 at 14:46 | Report abuse |
  18. BooBoo

    So if you treat the allergies, this article suggests that you loose the "prevention" benefits of allergies? I have been an allergy sufferer for ages, and finally it gotten bad enough I started allergy shots. But if I continue doing this, I have more chances of developing brain/spine tumor. What a choice... breath in Spring or tumor... urgh...

    February 7, 2011 at 11:45 | Report abuse | Reply
    • Donna

      I think the article was specifically referring to antihistamines use only, not shots.

      February 7, 2011 at 13:55 | Report abuse |
  19. Jenn

    I have allergies and ten years of allergy shots. Just had a grade two oglioastrocytoma removed last month. This article seems quite dubious.

    February 7, 2011 at 11:47 | Report abuse | Reply
    • Sickie

      I think the article kind of implied that untreated allergy suffers had less cancer, but medicines to reduce the suffering from allergies may actually be opening a door to cancers.

      February 7, 2011 at 12:10 | Report abuse |
  20. 1username2

    I think that this is a very interesting article because I have a lot of allergies. I never thought anything good would come from all of my allergies, but this could be something good. I think it is very interesting how allergies can relate to strokes. I think that this will make people that have allergies feel as if they don't have to worry about getting strokes.

    February 7, 2011 at 11:48 | Report abuse | Reply
  21. Rebecca

    I don't believe it! My son had allergies AND a brain stem gioma! I wish this theory was true, but I'm afraid it will just get everyone's hopes up!

    February 7, 2011 at 11:50 | Report abuse | Reply
  22. ron

    I lost track of my first college room mate for around thirty years. I had just finally located him, and we agreed to meet in the spring. 3 months passed, & he told me he had 'overnight' gotten weakness in one side. The doctor found he had glioblastoma multiforma (if I spelled that right), and I got to meet him exactly one time, then Kevin was gone. The reason I mention this, is that I remember from back at college, he was alergic to,,, well, everthing. He must have had literally 40 medications. And it eveidentally didn't help save him.
    He didn't last a year.
    I miss my old friend, and just feel really fortunate & blessed that I was able to see him before he was gone. Later, one of his closest friends told me he'd been understandably depressed & my visit had really helped. Cheers!, Kevin. You are missed..

    February 7, 2011 at 12:00 | Report abuse | Reply
  23. Jen

    You need to remember that this seems like a very preliminary study. As stated, it only shows a correlation. And just because something is correlated doesn't mean that it will happen all this time – that's how you'll get people with allergies and brain tumors. What' important to note are the implications of this study. The next step will probably be using mouse models to test this hypothesis. The connection between allergies and the brain may seem weird, but here's a fact: histamine is not only used by the immune system, but also by the brain. The brain uses it as a communication tool. This is what we need to look into.

    February 7, 2011 at 12:24 | Report abuse | Reply
  24. no one in particular

    what if you're allergic to brain tumors?

    February 7, 2011 at 13:22 | Report abuse | Reply
  25. Moodyme

    As an allergic person , I rejoice.

    February 7, 2011 at 13:34 | Report abuse | Reply
  26. Glioma Widow

    My husband died from a GBM and had environmental allergies all of his life and lived on antihistamines both Spring and Fall!!

    February 7, 2011 at 13:49 | Report abuse | Reply
    • Moodyme

      I once asked my neurologist whether a particular anomaly in my brain was "caused by" or "caused" my migraines, or was simply "associated with." he settled on "associated with," which another way to say that the answer is not yet know. So it is with allergies and a low incidence of gilomas.

      February 7, 2011 at 14:23 | Report abuse |
  27. sealchan

    Yes, this study is only a correlation but it may help point to a factor that increases the risk of a glioma. I haven't studied cancer at all so I do not know what is known or not known about the origins of cancer or gliomas. But I do have a grandson with a pontine glioma...typically these are very aggressive but so far his is not. In another month he will have his second MRI so that we can determine if there is any appreciable growth taking place. My grandson also has Prune-Belly syndrome (aka Eagle-Barrett syndrome) which has put him in the way of getting a regular dose of at least two antibiotics since he was born. I have heard that allergies tend to form in those who live in over-sterilized environments. So needless to say this article has caught my attention. Perhaps my grandson developed a glioma while he was in the womb but once he was born his regular dose of antibiotics plus however this has impacted how his immune system functions has kept his glioma in check?!

    February 7, 2011 at 14:38 | Report abuse | Reply
  28. OvernOut

    Asthma is tied to allergies, but if you don't treat the asthma, you could die of an attack. I had an aunt who lived before asthma treatments were available, this woman wheezed and gasped her way through a short life. She developed heart disease and that's what killed her. "Heart disease" should be just as scary as "cancer".

    February 7, 2011 at 14:53 | Report abuse | Reply
  29. Vera

    Please exercise a for at least 2.5 hours a week! This will save your life! The World Health Organization issued a press release regarding the necessity of exercise: http://www.who.int/mediacentre/multimedia/podcasts/2011/cancer_20110207/en/

    February 7, 2011 at 15:13 | Report abuse | Reply
  30. Ankhharu

    what about the tumors that having allergies causes? I have chronic allergies and have had 3 tumors in my ear thanks to these allergies.

    February 7, 2011 at 17:46 | Report abuse | Reply
  31. zona jones

    People with allergies have very strong immune systems...that's what causes all the allergic responses (an overly strong immune system that reacts and attacks too many things). That's the bad news but also the good news. Those oh so strong immune systems apparently fight over cancers very well. I'm an allergy sufferer....I've been studyin' this stuff.

    February 7, 2011 at 20:59 | Report abuse | Reply
  32. Ram

    Whatever happens, happens for the good. There is a benefit even from a negative event. But it is highly doubtful that allergy will cause health benefit. Reducing the probability of having brain turmor is not a health benefit. Allergy and all other immune-based deficiencies can be fixed by following hygene rules, having balanced diet, exercising regularly and having a peace in your mind (no stress, no worries, relax). Doing these will reduce the chances of having allergy as well as turmor.

    October 16, 2011 at 08:54 | Report abuse | Reply
  33. Kath

    Let me clear one thing up. Sickle-cell anemia is NOT a benefit biologically speaking. It means you have 2 lethal genes from both parents causing the sickling of your red blood cells. The benefit comes when you are a CARRIER, meaning you got one gene causing the sickling...but NOT a lethal double dose. By being a carrier, there is some advantage against malaria.... Apparently, Nature saw fit to take that risk, that some would get too much of a good thing and thereby mortally suffer, while others would be able to survive in malaria infested areas. It was a survival advantage over time. The benefits outweighed the risks of getting sickle-cell it would seem.

    July 1, 2013 at 10:56 | Report abuse | Reply
  34. Carry

    Individually, we can only offer anecdotal evidence, but personally, those anecdotes are our truth. Here's mine.

    My dad fell off a ladder at age 50 and broke a lot of teeth. He was well off, so he spared no expense restoring his mouth with implants, crowns, root canals. A few months later he decided to have a full medical check-up which included a bone scan. He was 100% healthy except for his allergies which seemed to be worsening, i.e. he blew his nose a lot. So the doctor recommended a monthly allergy shots for 8 or 9 months.

    Dad said the allergy shots made him feel lousy. I remember him running in the house shouting, "Get the Ben Gay." He said one of the side effects was a back ache, but thank goodness, that was his last shot... and his nose isn't runny anymore. But... the backaches continued. About 3 months later he went for a check-up. He thought he had something going on with his kidney. They did another bone scan. His entire skeleton was riddled with tumors. The doctors were astounded. There was no way he could get to stage 4 cancer in one year, while seeing a doctor regularly, no less, with no symptoms. (Lousy and back ache didn't count, apparently.)

    They biopsied poor dad many times. It was NOT colon, lung, liver, blood, prostrate, kidney or any other type of organ cancer. They never identified the source.

    Me, I think he was having an allergic reaction to the root canals, and the shots turned off his immune system, giving that deep dental irritation a chance to spew cancer into his system. Why do I think this? I had two root canals in 3 months of each other. They bothered me from day one, and I developed a slew of autoimmune conditions, along with worsening allergies. Then I developed neurological symptoms, and my MRI showed dozen of lesions on my brain. At 3 years, an Xray showed that the root canals had just about eaten through my jaw, and although my mouth looked good, I had a deep infection that was spewing poison throughout my system. After the root canals were removed and I had months of antibiotics, and 11k in dental work.... I was healthy again.

    Allergy shots? Not me! Nor any root canals or implants, thank you.

    July 21, 2013 at 12:52 | Report abuse | Reply
  35. jual besi beton

    US deficit > $400 Billion. US debt > $18 Trillion. Bernie's approximate proposal costs are approximately $18 Trillion over 10 years. If we continue the path we're going down right now by the end of 2025 we'll be $40 Trillion in debt (18 Trill + 18 Trill+ (.4Trill *10Years)). Over simplifying, but watch out the dollar might be on a road to collapsing. I hate saying it, but if Bernie is the nominee, I'll probably have to vote republican.


    March 28, 2016 at 05:43 | Report abuse | Reply

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