Medical Matters: A European Directive came into effect last week that will give some cheer to those who suffer from food allergy. It provides legislation for improved labelling of food products offered for sale within member-states.
Consumers will now be better informed concerning the exact nature of the ingredients. The most common food allergens, which together account for some 98 per cent of all food allergic reactions, have been targeted. These include: gluten-containing foods (wheat, rye, barley, oat, spelt and kamut), crustaceans (shrimp/prawn, lobster, crab), egg, fish, peanut, other nuts (almond, hazelnut, walnut, cashew, pecan, Brazil, pistachio and Macadamia), soybean, milk, celery, mustard and sesame.
Sulphur dioxide and other sulphite preservatives, which can cause a serious exacerbation in 5 per cent of asthmatics, must also be declared on the label if it is present in amounts of 10 mg/kg or per litre. Although the directive is in force as of November 25th, it will not apply to foods labelled before this date.
The incidence of food allergy peaks in early life, with some 8 per cent of toddlers affected to some extent. Many of these will grow out of their allergy but others have a more persistent and potentially dangerous problem. Some 3.5 per cent of adults also have food allergy, a number which appears to have increased in recent years.
True food allergy, in both children and adults, refers to individuals who have sensitised to specific food allergens, usually food proteins. They produce allergy antibodies (called IgE) that will recognise the allergen at next contact and react to it. The presence of these antibodies can be detected by a blood test or inferred by a skin prick test.
Egg and milk are probably the most commonly diagnosed food allergies in Irish children; whereas fish is a more common allergen in Spain, and sesame is commonly implicated in Israel. Peanut allergy appears to be on the increase across all age groups and on both sides of the Atlantic. Allergic individuals, when they come into contact with their allergen, react in a variety of ways. Symptoms range from a trivial if sometimes frightening rash, to a much more serious life-threatening reaction called anaphylaxis.
An estimated 150 deaths from food-induced anaphylaxis occur each year throughout the EU, but that excludes cases that have not been recognised as such and whose death was attributed to some other cause. A retrospective analysis of 13 million children in the UK over 10 years identified eight children who died from anaphylaxis. In the past two years of this study there were an additional 55 serious reactions, six of which were considered near-fatal. Thus, the risk is estimated at one fatality per 800,000 children a year.
Risk is highest in patients with poorly controlled asthma, and in those who do not receive the correct treatment at the onset of an attack. For this reason, patients at risk carry a pre-loaded adrenaline syringe for self administration while they seek medical help.
Anaphylaxis can be triggered by invisible allergen. That explains the apprehension these people feel when they are faced with a food of unknown content, or with the blank expression of a waiter who does not know what they are talking about. Because allergic reactions can be instantaneous and rapidly progress to life-threatening asthma and/or cardiovascular collapse, people with known food allergies are advised to take care to avoid contact with even minute amounts of allergen. This may appear a simple task but experience proves that even well-informed patients have a 40-50 per cent chance of accidental exposure to their allergen each year. Adequate labelling of food products will go a long way to reducing these accidents.
But the allergic patient still has several obstacles and dangers that need to be addressed. For example, during a recent trip to a supermarket I was dismayed to see a large hand-written placard standing guard at the entrance to the bakery section. It read "All these products may contain nuts."
This self-protective style of retailing must be discouraged. Manufacturers should separate foods which are known to contain nut (or other allergens) and ensure that production lines for other foods are segregated such that accidental contamination with unwanted food allergen is physically impossible. Allergic patients do not want to know that a product "may contain traces of"; they want to know whether it does or doesn't. Another source of concern is the occasional accidental large scale contamination of foods with undeclared allergen, such as the "strawberry yogurt" carton that is accidentally filled with hazelnut yogurt.
Let me close with a plea to the catering and hospitality industry. The gentleman sitting at table 12 is not a crank. He has anaphylaxis. For this reason, he has politely requested that his meal be prepared with special care to avoid contamination with his known food allergen. This will be inconvenient for the chef who will have to use a separate chopping board and other utensils to ensure a safe meal is delivered to his client. In many ways, the chef will need to adopt the same skills that he already employs to avoid food poisoning. Caterers have achieved gold standards of quality in recent years along the microbial line. Now they have to do the same for food allergens.
• Dr Joe FitzGigbbon is a specialist on allergies who practices in Galway