The relationship between hay fever and oral allergy syndrome
In addition to the allergens – pollen, mould, dust, feathers, animal dander, chemicals and environmental pollutants – edible items can also provoke a reaction in susceptible people. This is a condition known as oral allergy syndrome (OAS), also sometimes referred to as the pollen-food allergy syndrome. The symptoms arising are largely restricted to the mouth and throat. Eating fruit, for example, has been reported to result in itching of the mouth and throat, mouth ulcers, swelling of the lips and/or tongue, hoarseness and a need for compulsive throat clearing. When the oral allergen is cooked or canned, the reaction doesn’t appear to occur.
Foods of the compositae group – the aster family of plants – such as nuts, celery, lettuce, artichoke, chicory, sunflower and safflower can give rise to acute allergic reactions with serious symptoms such as swollen throat and vocal cords, bronchial asthma, urticaria (nettle rash) and sometimes even anaphylactic shock.
Having an allergy to a specific type of pollen can make you susceptible to developing an allergy to a particular food or foods. Indeed, the following observations have been made:
• People who react to silver birch pollen (prevalent in Europe and Asia) often develop an oral allergy to apples, cherries, peaches, carrots, celery, walnuts, peanuts and hazelnuts.
• People who are allergic to grass pollen (dominant in many areas of the world) tend to develop an oral allergy to melon, watermelon and tomatoes.
• People who are allergic to mugwort (prevalent in Europe, Asia and Africa) often develop an allergy to apple, carrot and celery.
• People who react to ragweed (prevalent in North America) tend to develop an allergy to honey, bananas and melon.
In the same way, people who are allergic to latex – latex gloves, for example – are prone to developing allergies to bananas, kiwi fruit, avocado and chestnut.
In a study of 1,129 adults with hay fever and/or bronchial asthma, a substantial 24 per cent experienced allergy symptoms on eating or even handling certain foods – hazelnut, shellfish and apple being the worst culprits.3 Interestingly, the same researchers also discovered a link between an allergy to birch tree pollen and food sensitivity to apple, cherry, nuts, peach, carrot, plum and new potato. In allergy tests, it was seen that those with the severest allergy to birch pollen were sensitive to a wider array of foods. In addition, the study found a correlation between intolerance to acetylsalicylic acid (a food additive) and sensitivity to foods such as nuts, strawberries, chocolate, almonds, rosehips, green pepper, milk, cabbage and eggs. Considering the large amounts of food additives consumed in the average Western diet, it is no wonder that so many people become sensitive to certain foods.
It might seem surprising that even a natural food such as honey can trigger a strong allergic reaction in people with hay fever, as research has shown. In further tests, this was explained by the large concentration of sunflower pollen (23.6 per cent) found in the honey, and it was this that was responsible for provoking the reaction.4 Allergic reactions from other natural foods such as sunflower and safflower – from which many oils on our supermarket shelves are produced – are also thought to be caused by pollen.
A food elimination programme
Discovering whether you are sensitive to a particular type of food can be very difficult; tests are available, but each can be criticized if one deliberately sets out to do so. The only certain way to prove the case is via a food elimination programme. As this requires the elimination of one food at a time, then waiting to assess your body’s response, it would take many months to find your sensitivities. For this reason, attending an allergy clinic is advisable.
Initial withdrawal reaction
If you already suspect, however, that certain foods are causing you problems, a food elimination programme can be a good idea. Withdraw one food at a time from your diet for one month. Assuming that the food you eliminate is indeed a problem, there is often an initial withdrawal reaction – fatigue, headaches, twitching and irritability are normal, and can persist for up to 15 days. Drinking around five pints of water each day can help to reduce these symptoms. This can also aid detoxification and help to flush any residual offending foods through the digestive system.
Halfway through the elimination programme you may find that you become hypersensitive to the culprit food and that eating it unwittingly can cause a severe reaction. Dining out during this period may be inadvisable, as you never know exactly what ingredients have been used. If you are eating out, ask the chef, not the waiter, if you are at all uncertain of the ingredients.
A pleasing symptom of food elimination can be weight loss, if you were overweight. The reason for this is that many people with food sensitivities have an excess of fluid distributed throughout their bodies. When they eliminate certain suspect foods, this fluid quickly drains away.
While you are following a food elimination programme, make sure that you continue to eat enough staple foods such as bread, cereals, rice, pasta, fruit and vegetables. Cutting down too much can lead to nutritional deficiencies. If you need to eliminate some staple foods from your diet, ensure that you take a multivitamin and mineral supplement to prevent any possible deficiencies.
Reintroduction of excluded foods
Towards the end of the month you may be feeling better than you have for a long time. The sense of well-being can be so great that you won’t want to bother to reintroduce the excluded foods. But if you do wish to reintroduce them, the following procedure is suggested:
• Day 1: In the morning, reintroduce a small amount of an eliminated food (not a full-sized portion). Do the same later in the day and take note of any symptoms.
• Day 2: If you fail to experience symptoms, repeat the exercise. Once again, take note of any symptoms. If you get through the second day, this is really good news. Now wait two more days before you can safely reintroduce this food into your diet on a fairly regular basis.
Repeat this four-day ^introduction procedure with each food eliminated. Any reintroduction side effect should have occurred within this period. Unfortunately, you may find that some foods will always cause an adverse reaction, so it is wise to withdraw them from your diet completely. In the meantime, continue to eat sensibly. Try not to indulge too much in the foods that previously caused problems. And remember, if in doubt, leave it out!