Wednesday, 11 August 2010

Food Allergies - Fact, Fiction and Fad

There are two common responses when the subject of food allergies comes up. The first, mostly but not entirely from older people, is "Stuff and nonsense. They didn't exist when I was young, we ate whatever was put in front of us. You don't see starving people in the third world with allergies". The second is: "I feel much better and have lost lots of weight since I stopped eating wheat. I know I'm allergic/intolerant because I sent my poo/blood/hair away to be analyzed".

According to one source, 25% of adults think they have a food allergy although studies show that only about 2% really do. Which means that at least nine out of ten are making a big fat fuss about nothing. Recent news said that up to 8% of children now have allergies although a spokesperson from Allergy UK said: "Parents often look for alternative ways to diagnose their children, using tests which aren't scientific at all. Parents tend to think it's an allergy without taking proper medical advice".

It's mostly middle class people with a bit of spare cash who have latched onto food allergies and intolerances (the two are often used interchangeably). Not the life-threatening A&E kind of allergy but the feeling a bit bloaty and tired, self-dramatizing kind which are not allergies at all. Some people will happily say they're 'a bit allergic' to something without any medical evidence whereas they would never say 'I'm a bit diabetic' and not bother going to the doctor. One reason people might well feel better and lose weight by giving up wheat is that by not eating bread, pasta, pastry and pizza they are also cutting back on the high fat, high salt ingredients that go with them - cheese, highly salted meats, mayo, creamy sauces and so on. Or maybe they really are lactose intolerant and have accidentally cut most dairy out of their diet by giving up these foods. That's the trouble with self-diagnosis.

Saying 'I'm allergic to dairy' or 'I'm gluten intolerant' has become a bit of a middle-class mantra, not that different from telling people your star sign in some circles, as if that makes you more interesting and special. People are more than happy to discuss the details of their alleged intolerances in company where they wouldn't dream of mentioning an ingrown toenail or dandruff - two equally unpleasant but minor complaints. I've heard lengthy conversations about how cutting something out of a diet has changed someone's life, usually followed by a discussion of how they found out they had an allergy/intolerance. Inevitably, this does not involve a visit to the doctor. It involves posting some bodily fluid or excresence off for analysis. There are often endless conversations sharing the love and comparing notes on what foods they can't eat and how they got 'diagnosed'. While eating dinner. Of course, the host/ess has been thoughtfully supplied in advance with a list of all the things the guests can't eat.

A food allergy is an adverse immune response to a food protein. The body identifies a protein as something threatening, the immune system thinks it's under attack and triggers an allergic reaction which can range from mildly unpleasant to life-threatening.

In answer to the people who think that allergies are a modern fad - they're not. In the olden days, anyone with a serious allergy wouldn't make it through childhood and in days before the NHS and proper testing, the cause of death mostly went undiagnosed. The same still goes for parts of the third world. These people are often heard saying things like a certain food doesn't agree with them or 'I like it but it doesn't like me' without thinking that this could be a mild allergy. But going on and on about them is a modern fad, part of a more general obsession with food in our over-stocked culture. It's what used to be called being a fussy eater, perhaps followed by a smack on the bottie that quickly put paid to that bit of wilfulness.

An intolerance doesn't involve an immune reaction. It happens when the body is unable to deal with a certain type of food, usually because it doesn't produce enough of the chemical or enzyme needed to digest it. For example, a shortage of the enzyme lactase causes problems breaking down milk sugar (lactose) into simpler forms that can be absorbed into the bloodstream. There's a strong genetic pattern to food intolerances. Lactose intolerance is less common among northern and western Europeans (10 to 15 per cent are affected) than in Asian, African, native American and Mediterranean populations (70 to 90 per cent are affected). Symptoms include nausea, bloating, abdominal pain and diarrhoea, hours or days after. Which are pretty unpleasant. But those nasty squitty, pukey symptoms don't tend to get mentioned in dinner party conversations, which are more likely to involve weight loss and the person's skin improving. If you have regular cramping and throwing up, you'd probably hightail it to the doctor.

There are plenty of ways to get diagnosed. One involves getting medical advice. The rest don't. Some of these are pretty expensive, often hundreds of pounds. NICE has issued draft guidelines for doctors on diagnosis and treatment of allergies, which contain the advice 'Do not use the following alternative diagnostic tests in the diagnosis of food allergy: vega testing, applied kinesiology, hair analysis'. The guidelines also say that 'it was reported that many people with allergies practice self-care, using alternative sources of support rather than NHS services (for example, complementary services with non-validated tests and treatments)'.

Briefly, kinesiology uses 'energy* fields' in the body to diagnose allergy and intolerance, vega testing involves measuring electromagnetic conductivity in the body using a Wheatstone bridge galvanometer - the same device Scientologists use outside their centres to 'test' passers-by. Hair analysis tests for heavy metals that allegedly cause allergies or involves dowsing - swinging a pendulum over the hair; an allergy is diagnosed if an altered swing is noticed. And then there are the poo samples. Post your poo off to a lab in the UK or US and find out how many different foods you're allergic or intolerant to. As one UK hospital states, samples more than 8 hours old will not be processed as they have degraded too much, so sending poo through the UK postal service to another city, let alone to the States, is hardly going to ensure it arrives in prime condition. And I really don't want to think about what collecting your own poo sample involves. Or what postal workers might make of poorly wrapped packages.

There are some excellent analyses of why all these alternative testing methods are nonsense on stilts on Quackwatch and Holford Watch.

If you really are allergic or seriously intolerant, it can be very unpleasant indeed. If you think you might be or that your child is, see a doctor. Otherwise, kindly shut the fuck up. Or am I being intolerant?

* As soon as you hear 'energy fields', you know you're in quackland.


  1. You may well be right, but you completely skipped secondary allergies, which is a function of adaptive immunity. Many 'intolerances' are secondary allergies -- the kind of allergy which is said to happen to your 'favorite foods.' It irritates your system a little, you don't really notice, you keep on eating it, and after a while your immune system learns to recognize and attack the proteins in the substance (and consequently the cells in your digestive tract). This is what happens to individuals who have celiac disease, which is not an allergy but nevertheless involves the immune system and can have life-threatening consequences.

    Your body can also mistakenly recognize similar proteins (for example if you have a casein allergy you are to avoid soy protein for a period of time so the body doesn't start reacting to that too).

    There is nothing wrong with going on an elimination diet, then 'testing' with foods to see if something bothers you, and declaring yourself 'intolerant' if such does happen. It certainly won't hurt you to avoid ingesting things that you think are making you hurt. That is the result of observation on an individual basis and I don't think it's fair to lump it in with 'quackery' like hair or stool testing.

    Many people simply aren't in the habit of noticing how their bodies react, or they take an over-the-counter remedy (like an antacid) that ultimately helps the problem snowball. Mandating that you must see a doctor (and they can't always diagnose properly either) takes the habit of observation out of peoples' daily orbit and helps make them prey to the kind of scam you describe.

  2. If you have a very clear reaction to one certain food and feel better by cutting it out, then that would be a simple solution. The problem is, as I said, that it might not be that clear cut; you may just feel better on an elimination diet because you're eating more healthily, for example.

    I don't think that running to the doctor is always the solution and I know that some allergies/conditions are hard to diagnose. Being aware of how your body works is a good thing, but only up to a point.

    My main point was about the type of people who self-dramatize when they really have nothing wrong with them. I said 'there are two common responses', I didn't say these were the only ones.