Citric Acid Intolerance

Citric acid intolerance is not the same as citrus allergy. Citrus allergy sufferers respond to substances specific to citrus fruits such as limonene or specific proteins found in the fruits, whereas citric acid intolerant people react only to citric acid, which is found in a number of fruits and even some vegetables, and is used as a food additive.

Citric acid intolerance is not a "true" food allergy - that is, it's not an autoimmune response to a chemical in food. Intolerances occur when the body lacks some chemical or enzyme necessary for it to properly digest a particular substance: one of the most common is lactose intolerance, which is caused by a genetic difference which makes the body of a sufferer unable to produce the enzyme lactase. Currently, I don't know what quirk of body chemistry makes people intolerant to citric acid - but I do know that the problem runs in my family!

It's important to manage food intolerances as the body's negative response to the food in question can damage the lining of the gut and impair digestion (particularly true of coeliacs). This in turn can predispose the sufferer to acquire true allergies, as poorly digested food proteins enter the bloodstream through the damaged gut wall and the immune system is exposed to unusually high levels of them.

Most commonly, by fermenting cane sugar or molasses in the presence of a fungus called Aspergillus niger. It can also be obtained from pineapple by-products and low-grade lemons, but basically, most of the citric acid that's used as a food additive is mould extract. (Yeast allergy sufferers have to avoid it for exactly that reason, apparently). Sounds a lot less appetising when you think about it like that, doesn't it?

Citric acid is an appallingly common food additive: it has an enormous number of uses from providing a sharp, sour flavour to preserving and even acting as a catalyst to other preservatives. However, with careful attention to ingredients and a willingness to pitch in to cooking for yourself, it is possible to completely avoid citric acid. Making your own desserts and sauces is a great way to avoid it, because it's most common as a preservative in sweet foods and those containing fruit or tomatoes. Shop-bought fruit flavour yoghurts almost invariably contain it, for example, but home-made desserts and smoothies using non-citric fruit along with plain yoghurt, citric-free ice cream, milk, or apple juice make a delicious and additive-free alternative. Readymade sauces, especially pasta sauce, are another enormous offender, so making your own fresh food is a must. (Pasta sauce is somewhat dicey since tomatoes do contain citric acid, though in relatively small amounts: you may be able to cope with tomato-based sauces in moderation. However, some varieties of canned tomatoes contain citric acid, so check the label before buying: organic canned foods are more often additive-free.)

"Going organic" is another good general tip for citric acid intolerants, since the organic food philosophy is to minimise the use of all food additives as well as eliminating pesticides and other agrochemicals. Organic pre-prepared foods are likely to use fewer additives than non-organic foods, but conversely they also won't keep as long, and it's still vital to check the label for citrus juices before you buy.

Eating out can be a chore for any allergy or intolerance sufferer, but one handy way to check out in advance what you're likely to need to avoid is to Google for recipes of dishes likely to be on the menu at the place you're planning to eat. Doing this can give you a good general idea of how much citric-containing stuff your chosen cuisine tends to contain, and can help you avoid restaurants where you'll have little or no choice, but of course you should always ask in the restaurant too to make certain that their special house recipe is still OK!

I have a personal theory, which I haven't yet proved, that vitamin B5 or B vitamins in general may help ameliorate the symptoms of having accidentally eaten citric acid. I'll be testing this out in the future so please do check back again; I also hope to have more information about whether citrates (salts of citric acid which are also used as food additives) also provoke a reaction.

I'm 28 years old at the time of writing, and have suffered from occasional bouts of IBS since coming down with gastroenteritis in 2001. In early 2006, the IBS returned, but was far worse than previously - I found that about half the time, my stomach would just shut down on me completely half way through a meal and I'd feel completely unable to eat any more. To begin with I was very confused and concerned by the fact my digestive system appeared to have completely changed the way it worked, for no readily apparent reason; I did the usual things that help my IBS, such as eating easily digested foods, cutting out alcohol, fat, sugar, and foods containing very large amounts of roughage: I patiently consumed yoghurts and drinks containing friendly bacteria, but all to no avail. After some three months of this I eventually went to my doctor to ask if I might have a food allergy, and explained that there's a history in my family of reacting to very sour citrus fruits, or large quantities of them. She explained that it was likely I suffered from the same thing, and got me to keep a food diary. It took less than a week of analysing the content of foods I reacted to before I realised that citric acid was the culprit: any food containing it in anything other than tiny amounts caused me to bloat up enormously with painful excess wind, overstimulated my bowels and hence stopped me feeling hungry due to the nausea caused by my intestines doing gymnastics.

Cutting citric acid out of my diet to make sure the effects vanished and I'd identified the right problem was the obvious next step. It's not easy to do at all because citric acid is one of the most common additives around (see the 'Managing citric acid intolerance' section above), and I began to develop a real appreciation for the difficulty coeliacs and yeast allergics suffer in suermarkets! But it is possible, especially if you're willing to cook and bake yourself instead of relying on convenience foods and readymade stuff. After a few misfires and accidents with foods I was used to being 'able' to eat turning out to contain citric acid, I found that the painful wind and inability to eat subsided; a few weeks after that I discovered I'm also lactose intolerant, and after cutting cow's milk out too I was left only with the IBS. You almost never think you'll welcome IBS, but after three months of anxiety and weight loss, it was as big a relief as coming home after a stressful trip!

As far as I can tell there's very little information available about citric acid intolerance, apart from the fact that everyone who does comment on it says "well, it's very rare". I'm planning to put any information I do find up on this page, so please do keep checking back.