A Quick Look at Food Allergies and Intolerances
In recent year, a lot of ideas have become strangely popular on this place that we call the Internets, one of those is concern over various food allergies and intolerances. As I’ll discuss below, not only are true food allergies and intolerance two totally different things, there is a lot of nonsensical information being thrown around about food allergies.
What seems to have happened is that one person stated that certain ideas were true and a bunch of people who didn’t know any better simply started repeating those ideas until they became an accepted ‘truth’. Unfortunately, science says different and that’s what I’m going to look at.
The most common one that seems to be constantly repeated is that if you eat the same food (usually protein since most true food allergies are caused by proteins) continuously, you can give yourself an allergy to that food. This happens to be utterly wrong as I’ll show below.
There are other silly ideas, one of the dumbest I’ve seen of late is that you can cure a food allergy by not eating that food for 6 weeks. This is not only wrong but potentially fatal. True food allergies (again, I’ll discuss what this means in a second) never go away; if someone has a true allergy to a food, they can’t ever eat that food again for all practical purposes.
Actually, that’s not entirely true, one weird study showed that children with peanut allergies could eventually get to where they could eat half a peanut but it took months and months of feeding them like 1/4 peanut to get them to that level. Hooray. For all practical purposes, a true food allergy never goes away and the idea that abstaining from that food will make it go away is simply absurd.
Since most food allergies occur in response to protein foods, I’m actually going to simply be excerpting the section from The Protein Book about food allergies and intolerances. For anybody who’s interested, I’ve included the references cited in this section at the end of the article.
Food Allergies and Intolerances
To finish up this chapter, I want to make a few comments about food allergies and intolerances, which I touched on above in the section on dairy foods. Commonly, the terms food allergy and food intolerance are used interchangeably although they actually represent very different phenomena (40).
Food intolerance, such as lactose intolerance from dairy products, typically occurs due to a lack of appropriate digestive enzymes and this tends to cause upset stomach, gas, bloating or diarrhea. At worst, food intolerances typically cause some discomfort but no real danger.
In contrast, a true food allergy generates an immune reaction in the body. This is potentially much more severe and can cause respiratory, stomach, skin and cardiovascular symptoms; anaphylactic shock and death can also occur in extreme cases (40). True food allergies are typically caused when small amounts of proteins enter the bloodstream. This can occur during childhood when the gut lining isn’t fully developed or later in life due to a compromised stomach barrier. Some allergens can also enter the body through the respiratory system.
While technically any food can cause a true allergic response, protein foods tend to be the most common culprits with milk, egg, peanuts, tree nuts, some fish and shellfish being the most common causes of allergies (41). Gluten, a protein found in grains such as wheat, barley and rye, is also a common source of food allergies (42). Gluten allergies can be especially troublesome for athletes with high caloric and carbohydrate requirements since grains cannot be consumed; increasing commercial availability of gluten free foods can help to ensure adequate calorie and carbohydrate intake.
True food allergies are thought to occur in 3-4% of adults. There are a number of different ways to determine the presence of a true food allergy but, from a practical standpoint, if eating a given protein source causes problems of the sort described above, that tells the athlete all they need to know. For the most part, there is little to no treatment for true food allergies; avoiding the problem food is the best and only option (40).
References:
40. Ortolani C and Pastorello EA. Food allergies and food intolerances. Best Pract Res Clin
Gastroenterol. (2006) 20(3):467-83.
41. Sicherer SH and Sampson HA. 9. Food allergy. J Allergy Clin Immunol. (2006) 117(2
Suppl Mini-Primer):S470-5.
42. Schuppan D et. al. Celiac disease: epidemiology, pathogenesis, diagnosis, and
nutritional management. Nutr Clin Care. (2005) 8(2):54-69.
Summing Up
So hopefully the section above helped make the distinction between a food intolerance and a true allergy. True food allergies are rare and can be fatal like any true allergic reaction. Eating that food causes a massive immune response and this can cause people to drop dead.
This is not a joke, children with peanut allergies who are given a food with even trace amounts of peanuts can go into anaphylactic shock, have trouble breathing and can die. Contrast this to when someone has a lactose (milk) intolerance, drinks a glass of milk and gets real gassy. They are not the same thing but people confuse them all the time.
As well, food intolerances are reported at something like ten times their actual rate of occurrence; people eat something and don’t feel good and assume they have an intolerance when they really don’t.
And, as discussed above, true food allergies don’t occur because you eat a given protein source too often. An allergy occurs when a bit of undigested protein gets into the bloodstream and causes the body to mount an allergic reaction to it via the immune system. Since the gut lining is set up to avoid this, the only way that a true food allergy can usually occur is if the gut lining is compromised. Under those conditions, small pieces of undigested proteins can slip through into the bloodstream and that’s when the problems start.
Various disease conditions can cause this to occur (and as noted children with undeveloped gut linings can develop food allergies because of it) but this pre-existing condition has to exist for a true allergy to develop. For example, there is a condition called leaky gut syndrome which is exactly what it sounds like, the gut leaks stuff into the bloodstream; this can cause all kinds of problems.
And once a true food allergy exists, it’s yours forever. The immune system is amazing in this way, remembering how to mount a response to offenders basically forever (this is the basis of immunization of course, give the person a small case of a certain disease so that the immune system ramps up, and then they can fight off that disease in the future). So once you have a true food allergy, you have it for life.
It is certainly not my area of expertise but people who fear that they may have a food allergy can get explicit testing for it done. However, as I noted above, if you eat something and nearly die, you know all you need to know anyhow. This is true at least in the case of severe food allergies. Of course, it seems that it is possible to have mild food allergies (which are probably more like intolerances) and getting tested for those may be useful if someone suspects a problem.
If for no other reason, food intolerances seem to be able to generate a stress response and this appears to cause water retention in some people (in addition to just generally not feeling very good. I have a hunch that the whole idea of ‘eating foods you’re ‘allergic’ to stops weight loss’ is probably due to this mechanism: you start holding water due to a stress response and it masks fat loss.
Lyle,
Would atopic dermatitis (perhaps a bit of a catch-all phrase, but I figured it would be suitable here) be the result of a mild to moderately “severe” form of food intolerance? You often here about people with various skin issues possibly arising as a result of delayed reactions to particles of certain foods (which apparently got into the blood stream due to the gut lining being compromised, as you noted).
Just curious, as this seems to fall into that gray area where it’s not life-threatening nor is it something that causes any scale issues, but it can be rather vexing if you have skin issues that puzzle your standard dermatologist.
You mentioned that this isn’t a main area of expertise for you, so I understand if you don’t feel like adding any thoughts on this front, but even the most basic of your thoughts would be appreciated. As always thank you for the article and sharing this knowledge.
I think you incorrectly lumped gluten in with the allergies. Wheat allergy is a seperate issue from gluten intolerance( both celiac and non-celiac types), which is an auto-immune reaction.
Kadill
I did some checking online and it appears that both can actually occur. Celiac disease is a gluten intolerance but a true allergy to the protein present (as you state) appears to be possible as well. Thanks for the catch.
Lyle
The fact that an exposure to an antigen in a protein from food doesn’t cause a anaphylactic shock doesn’t mean that there’s not an immune response. You are right when you say it’s an not allergy but the immune system is very complex indeed and there are many ways in which it can react. Type I response and delayed allergies are just one type of reaction.
Gluten intolerance doesn’t cause celiac disease only. It is related via HLA to many autoimmune diseases. Many people who don’t meet the actual criteria to get the diagnosis of celiac disease become symptom free of diseases such as lupus when they go gluten free – their intolerance manifests itself in other way. Same thing happens with proteins from dairy for many people.
Cordain may result a bit overzealous IMHO – but he’s got a reason,
Lyle,
You say that an allergy is for life, but they claim to be able to eliminate them:
http://lakeshorewellness.com/BioEnergeticStressTesting.html
What is you take on this type of stuff?
Lyle, this is a great post. Have you heard exercise-induced anaphalxia? I developed this last year (when I was 28), but it is only in combination with wheat. So, if I consume wheat products prior to exercise, I have an allergic reaction. Bad, too. Hives, sweating, stomach cramps, vomiting, increased heart rate… everything but swelling of the airways. Each reaction has gotten more severe, though, so I’m especially careful not to trigger another one.
Anyway, I ask because seeing an allergist was no help at all, either as to how it was caused or what to do about it, besides not exercising after eating. I normally exercise first thing in the morning before eating anyway, but there are times when I would like to go for a run in the afternoon, but can’t. If you can shed any light on this, it would be most appreciated. I’m especially curious as to how one can develop this allergy seemingly out of the blue.
Lyle,
You explained the difference between allergy and intolerance in the context of eating the same food continuously and that allergies can’t happen by doing that.
But can intolerance happen? If someone drinks milk/whey or eats chicken every 3 hours, for example, can he/she eventually develop some sort of intolerance to milk/whey/chicken?
Manoj
douaron1: They can claim what they want, unless they have a way to modify the immune system, they are making stuff up.
Palidor: Again, not my area of expertise.
Manoj: Of course not. An intolerance such as lactose intolerance is due to a genetic inability to produce the enzyme lactase. Eating that food won’t cause it. If anything, the opposite can occur: if you don’t eat a certain macronutrient for a long period of time, the body often reduces the enzymes responsible for digestion; when you reintroduce that food, there can be an acute period of intolerance while the body upregulates those enzymes.
Angela: Ah, the old, just because you don’t notice it doesn’t mean it’s not there argument. Would you like to pet my invisible unicorn? Because that’s what your argument amounts to: even if there is no external manifestation of an allergic reaction, there can still be one. We just can’t measure it but it’s still there.
Lyle,
Thank you for clarifying it!
Manoj
Thanks for bringing attention to this issue. I have an intolerance for wheat that went unnoticed until I was 33. I was never able to get below 12% BF while eating wheat regularly. Standard allergy tests never found it, but now that I’ve eliminated it from my diet there is quite a difference. My body fat has gone down and I can tell if I eat something with wheat in it (boating).
It may be true that only a single digit percentage of people have a food allergy that will cause them to become deathly ill, and anyone suggesting that they toy with it is foolish. But I’ve seen numbers suggesting as many as 70% of people have a food intolerance. I would recommend if you are suspicious of a digestive intolerance that you cycle eliminating foods with common allergies from your diet one at a time for at least three weeks. If there is an improvement leave it out for good. Some of the most common food allergies/intolerances are dairy, wheat, eggs, soy, seafood, nuts.
There are many experts who practice at a very high level who believe that intolerances and mild allergies are built up from chronic consumption of particular food items. Eggs are one of those foods. The false simplification that you draw from this is way out of bounds for what I normally read on your blogs. Just because you don’t go into Anaphylaxis and die doesn’t mean continued consumption of a food product is good for you. Everyone who is concerned with their health needs to pay attention to this issue while understanding that it is very complex.
Cool stuff. I noticed I break out with certain dairy products (ice cream, any % milk, cheese) but not yogurt? What’s up with that?
All that I’ve read about acne and food is that there is no scientific correlation between the two. I’ve taken no chances and have since switched to almond and rice milk but missing out on some wicked cheeses and of course a great summer time treat. Arghhh…
Hi Lyle, I love your website and am slowly reading through all your articles. I have struggled with what I though were food allergies for the last ten years. I found that everytime I went on a ketogenic diet that as I started to add back low carb fruits and vegtables that I would break out in hives. Also SOMTIMES when I eat any red fruit or vegtable I would break out in hives but sometimes I wouldn’t. Same with latex in bandaids and underwear, very off and on again but often at times of high stress. If you think your stressed wait till you get home and think you are allergic to your underwear! When I would take off my underwear and bra there would be raised hives in the outlines of the garmets. It was driving me crazy becuase here I was having symptoms that seemed to be an obviously allergic reaction but not all the time which means it wasn’t a true allergy. My primary doc. wasn’t able to shed any light on it nor was any other medical professional I went to. I heard lots of change your laundry detergent. Ironicaly the only thing that seemed to help was to return to a appetite increasing, low nutrition sugar and flour diet that I was trying to escape. The last time I tried a ketogenic diet, it was 60 days before my wedding and I started with the hives again a day or so after I went off the diet. I was literally scratching as I took my vows. I figured that the high saturated fat and animal fats/protiens must be causing some sort of autoimmune or inflamation response in my body which is a shame because the ketogenic diet is the only diet that controls my cravings and appetite. I have in my past a long history with binging and compulsive overeating. However I couldn’t find any literature,personal stories or research where this was happening to anyone else. What are the odds that I am the only one who gets hives from atkins? Maybe I am a special, unique, itchy, overeating flower? Finally I posted this story on a nutrition forum hoping that there would be someone else out there who was experiencing what I had and a nutrionist wrote that it sounded like a histamine intolerance. I did some research and it fit. Unfortantly many low GI high protien foods are very high in histamine as are some of most nutrious fruits and vegtables, also high stress make the body produce its own histamine. I saw a research article from ASU that said that adults who get 2000 mg of vitamin C per day have a 40 percent drop in blood levels of histamine. So I am taking the C supplements and slowly trying to work in high protien foods/low GI avoiding the processed /aged meats which I think are the worst in general. I have been eating spinach, strawberries and tomotoes almost every day and so far no problem. I’m telling you all this becuase I looked for answers for years and no one ever mentioned that food intolerances can mimic true allergies which I think contributes to the confusion. I would love to know your opionion on this.
Regards Jennifer Soderstrom
In the opposite direction of the “abstain for 6+ weeks to possibly cure your allergy”, you can develop (temporary, I hope) “intolerances” for carbs or meat if you cut them out of your diet for long enough – something to do with the microflora in your digestive tract, I assume.
So, some people go almost completely no-carb (no-grain, at least), then have a bagel and feel sick, and decide that ALL ALONG carbs have been making them unhealthy, and they need to swear off permanently. Similarly vegetarians sampling meat and having a not-entirely-psychological adverse reaction.
Lyle – speaking of invisible mythical creatures: http://lesswrong.com/lw/i4/belief_in_belief/
Lyle,
With all due respect you may go back and re-read Angela’s post. You claim that auto-immune responses (your immune system seems to apparently attack itself and doctors/medical field can not explain it) are not “symptoms” that can be observed. What I believe Angela was saying is just because your body does not go into “shock” or you you not break out and “hives” does not mean that you are not having an “immune” response to something.
I am not saying that you are, but it is quite possible as I have three different autoimmune diseases, and it causes inflammation (which damages organs, causes body aches, etc.) causes skin outbreaks (psoriasis), causes arthritis (age 29), and my thyroid functions are out of whack…………..
Doctors can not explain what causes autoimmune disease………….but it isn’t so silly to consider that maybe it can be somewhat attributed to something you are ingesting………that does not show up on “allergy” tests.
I was told by my doctor that allergy testing that most labs do, is not exactly conclusive. It can say or not say you are allergic to something and the exact opposite is true. The best way, according to medical sites I’ve read, and to what the doctor said, is to cut out something………see if ur symptoms get better………if they do, don’t eat it…………
Unlike what most people think, the medical field does not understand all the underpinnings of the human body, let alone the immune system. We like to believe they do, but this assumption is just plain wrong. We may have narrowed down a few things, but when it comes to the immune system, especially auto-immune responses……….(gee, things floating around in the body due to “leaky gut” or the inability of ur body to “get rid” of it………..) is not such a crazy or ludicrous idea……..
I’m not saying it is accurate, but to say there is nothing to it, simply because the medical community (at least what you’ve posted, because the “medical community” rarely agrees on anything, and you can find doctors that claim almost the opposite of anything argument) claims that an intolerance is different than an allergic reaction……………doesn’t add up to me.
Especially when the medical community admits to NOT understanding what causes auto-IMMUNE responses. (tells me they do not completely understand the immune system.)
Thank you,
Nancy
P.S.
I am not a doctor, just read quite a bit of information that both agrees with your stance on the topic, and others that disagree……..and it isn’t so clear cut as you seem to state.
With all due respect: claiming that something exists in the complete absence of any measurable symptoms is about as useful as claiming I have a pet invisible unicorn: I can’t prove it but I can sure as hell assert that it’s there. It’s a meaningless statement.
Put differently, if there is truly an allergy or autoimmune of any significance, it should show up on a medical test. If it can’t be measured either
a. it doesn’t exist
b. it’s too minor to worry about
And just because holistic bozos can’t say ‘Well, it can still exist even if nobody can measure it’ and then sell you expensive placebos to fix a non-existent condition doesn’t make it any more real. Falling back on the ‘Modern medicine doesn’t have all the answers’ is a copout too.
Lyle
Lyle,
Have you heard of Kenneth Fine’s research on gluten? I don’t know much about other allergies, but I’ve long suspected that gluten has given me slight problems. Celiac disease runs in my family (I have 2 first-degree relative with it), yet my tests always came up negative — two blood tests for the gliadin antibody (the now “gold standard” Celiac test in doctor’s offices), and, yes, one biopsy.
I recently had a stool test with Kenneth Fine’s lab, and the tests did show gliadin antibodies in the sample.
So something that was undetectable by a standard medical blood test showed up in a more sensitive, but barely used, stool test.
Much of Dr. Fine’s research deals with both Celiac and non-Celiac gluten sensitivity (i.e. allergy). Current estimates yield about a 30% sensitivity incidence in the general US population.
While I agree with your logic that undetectable allergies either don’t exist or are too minor, I think it’s at least premature to put gluten (and possibly the molecularly similar casein) in this camp — you must realize that the blood tests for gliadin antibodies is terribly inaccurate and notorious for giving false negatives.
Gluten sensitivity is probably much more prevalent than we think. And it probably manifests itself in various, subtle ways (see: http://jccglutenfree.googlepages.com/).
I probably get just as annoyed with chronic self-diagnosers as you do. But at least in the case of gluten, the jury’s still out on it’s prevalence and overall significance in our population’s health.
Lyle,
do you ever get tired of youre own arrogance? Maybe mr.know it all should practise a bit more modesty. I know he is very angry and very hatefull at all the BS out there but…
Buck: The only people who get tired of it are the ones spewing ignorant bs. The people who are tired of being lied to and conned seem to be ok with it. Funny that.
Hypochondria (in the lay person’s concept) is rampant in our society, I think.
When I was a kid (don’t ask), people tended to want to be strong, say they were strong, and not admit to “weaknesses.” Now, it seems, people WANT to believe – uh oh, there we go again – that they suffer from many and myriad debilitating syndromes.
NO one (statistically) used to have “chemical sensitivities”, peanut allergies, and hundreds of never-before-heard-of problems. Now they are everywhere. Perhaps some are on the increase due to environmental and food reasons, I’m willing to say that. But I fear far more are in the head of the believer.
It’s like a coworker who claimed to have latex allergy, hence, when they painted the offices with latex paint, she had to stay away for a few days. Problem is, latex paint has none of that rubber stuff like gloves are made of. It just means a super fine particulate in suspension. She was hyper-religious and she was a liar. A lot going on upstairs, there.
I get mouth ulcers and swelling every time I eat bread, brownies, cookies. Allergy testing for gluten, wheat, yeast, corn, sugar, all come back negative. What could this be?
Something you should probably see a doctor about because, to my knowledge, mouth ulcers are not a symptom of food allergies.
Might have ‘em check for peanuts since that seems to be
a. common
b. something that is used in a lot of baking (e.g. peanut flower or some such)
I’m still not sure mouth ulcers are representative of an allergy, though.
Melissa ~ There could be something to the mouth ulcer-allergy link. My daughter is allergic to eggs and strawberries. The reaction to both are hives and swelling. The egg reaction is quite serious, although not anaphylactic. The strawberry allergy is very mild, however, so from time to time, she will have a small amount. Sometimes she gets a few hives but she always ends up with mouth ulcers the next day. I’m not certain if it is specifically an “allergic” reaction but I suspect it could be. These allergies were determined through a “scratch test” with an allergist.