Ever since my husband embarked on the Atkins diet a few years ago I’ve been wary of eating programmes that advocate avoidance of certain foods. The Atkins, you may recall, involved a lot of bacon-frying and eggs swimming in butter, which was why it appealed so heartily to blokes. Carbohydrates, as well as most fruit and veg, were out.

Sure, it worked — husband lost several stone. But it was such a pain: the unpleasant side-effects, all that extra washing up — plus the fact that people stopped asking us round for supper. Who could blame them: there’s nothing more irritating than spending hours cooking, say, a delicious lasagne only to have some lunatic scrape all the sauce off the pasta.

So the prospect of having my blood analysed against 115 foods to evaluate my immune reaction to each and every one before embarking on a five-week food exclusion programme in the interests of general health and weight loss didn’t exactly fill me with delight. But, hey, I’m here to learn.

At the Doctors Laboratory, just off Harley Street, a nurse led me to a small room. She took what seemed like several litres of blood (in fact it was two small phials), and we chatted. Apparently they get loads of “Immogenics” (the nutrition programme group) clients and this test is a popular one. I was in good hands, she assured me, smiling as I was ushered out; my results would be back in about a week.

Sure enough, a week later I was presented with a (laminated, very classy) chart, with all my “green” foods (ie, things I can eat) on the left and an initially encouragingly short but, on closer examination, troublesome list of “red” foods (reactive) on the right. The red list ranged from the baffling (lemons, courgettes, lettuce) to the classic (prawns, mussels) to the predictable (coffee); but it also, crucially, contained the following: buckwheat (top of the list), lentils, wheat, baker’s yeast, rice and oats. All the staples.

These foods, it was explained, were to be eliminated completely from my diet for the next five weeks, to give my immune system a chance to detoxify. Then they could be reintroduced one by one, for three days at a time (rather like you do when weaning a baby) to gauge my reaction. If nothing untoward happened, then I could start eating them again. Otherwise, I’d have to lay off for a while longer, possibly indefinitely.

At this point you may well be asking yourself: why? Well, according to the people at Immogenics, foods that irritate cause the gut wall to become porous. This means that undigested food (I think they mean microscopic amounts of food, not whole chunks of steak au poivre) can penetrate the bloodstream. This is the human equivalent of getting oil in your petrol tank: it clogs things up and generally makes you less efficient.

Instead of being converted into energy, more food is stored as fat. So not only do you feel headachy, lethargic and bloated, you put on weight more easily. And because your immune system is fending off undigested food, it has fewer resources to devote to repelling germs, so you get sick more often, too.

Not being a biologist I cannot vouch for the scientific accuracy of such a method (although Immogenics did present me with an impressive list of official sources); but in practice, and despite my grumpy scepticism, it produced some surprisingly pleasing results.

Early December might seem like the worst time of year to embark upon such a regime, but, actually, it was quite nice, as it meant I survived Christmas without the need for an elasticated waistband. The only aspect I didn’t feel able to comply with was the total ban on alcohol — but I did keep the champagne cocktails to a minimun. Otherwise, Immogenics make it as easy for you as possible. As well as a list of specialist food stockists (so you can source your wheat-free, yeast-free bread) and menu ideas, they also provide an eating-out guide to prevent you from accidentally ingesting a forbidden substance with your curry.

About a week into the thing I quickly realised a crucial fact: controlling what you eat automatically controls how much you eat as you become infinitely more conscious of what is passing your lips. Also, there are just fewer things on the menu. In my case, all bread, pastry and pasta, but also less obvious things such as pre-packed salads (onions, lettuce, lemon, remember?), sushi and soups (stocks almost always contain flour or yeast). Essentially my list left me with a choice of meat or fish, plus vegetables and fruit. On the upside, I had no issue with dairy or nuts — or chocolate.

Almost immediately I became aware of two things: I was eating less and I was less hungry. For the first two days I had a stonking headache (a standard reaction to cutting out caffeine, apparently). I was also as grumpy as hell, mainly because it was such a fag foraging for food during the course of a busy day. You can’t really eat a piece of mackerel with a healthy broccoli and carrot salad at your desk — that’s what sandwiches are for.

Thankfully a certain sandwich chain does a daily wheat-free sandwich that is not too inedible. That, with the help of small amounts of Green & Black’s chocolate (I’m allowed cocoa and sugar, OK?) just about kept me sane during the week. Evenings and weekends were fine, although perhaps a little potato-centric. I found myself eating more fresh fruit and vegetables than normal, especially around teatime, when they replaced the perennial slice of toast. Initially, I felt rather bereft; but within a couple of days I was just about OK with it — although I want to make it clear that an apple is not, and never will be, a valid substitute for toast and Marmite.

My persistence was rewarded. Within a week I began to feel lighter, that is to say not nearly as bloated, especially towards the end of the day. That terrible 4pm low, the one that inevitably leads to a Kit Kat and a cup of strong milky coffee, just stopped happening. I was also the only member of my family not to contract a revolting and lingering cold.

But, perhaps most interestingly, my lower back, which varies from sore to very sore to Jesus-where-are-my-Athrotec, calmed down considerably. This, apparently, is to do with the general reduction of inflammation in the body owing to the elimination of irritant foods. Generally, I felt much chirpier and, yes, I suppose I was “energised”. I also got back into a pair of old Whistles trousers that I haven’t worn since before I had my children. And that, if you’re me, is as close as it gets to pure joy. It’s just a shame that all my friends think I’m a crank.



Immogenics: visit www.immogenics.com or telephone 0845 6120612

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