Food allergies can have a big impact on quality of life, however many Irish people incorrectly think they have an allergy, when they actually have a food intolerance, a symposium in Dublin has been told.

Speaking at the event, Dr Aideen Byrne, a specialist in paediatric allergies at Our Lady's Children's Hospital in Crumlin and the National Children's Hospital in Tallaght, explained that a food allergy refers to ‘an immune reaction to food proteins'.

In other words, an allergy causes the immune system to react and this can involve different organs in the body, resulting in a range of symptoms. In some cases, an allergy can be so severe, it is life threatening.

A food intolerance on the other hand ‘refers to non-immunological adverse reactions to food components'. In other words, the immune system is not involved. Food intolerances tend to be less severe and are often limited to digestive problems.

Those with a food intolerance may even be able to eat small amounts of the specific food without a problem.

Dr Byrne told the symposium that the terms allergy and intolerance are ‘two distinct entities, which should not be used interchangeably'.

"Recent data has shown that 4% of Irish children have a (proven) food allergy. Risks associated with food allergy include nutritional deficiencies and severe life threatening reactions. Food allergies can impact quality of life and also lead to heightened anxiety and isolation," she commented.

This was backed by consultant immunologist at St James's Hospital, Dr Niall Conlon, who said that the distinction between allergies and intolerances ‘is vital as the diagnostic and management strategy for each is fundamentally different'.

The diagnosis of an allergy is based on the patient's clinical history and this guides what tests the patient will undergo. They may eventually have to undergo a challenge test, which involves exposing them to the suspected food and assessing the clinical response in a controlled setting.

"Despite being time and resource intensive, challenge testing is the gold standard in allergy diagnostics," said Dr. Conlon.

However, when it comes to food intolerances, there are no clinically valid diagnostic laboratory tests.

Dr Conlon pointed out that currently, information in this area ‘is dominated by alternative therapists and private medical practitioners'.

"This is in keeping with a lack of education about allergy for healthcare professionals and a lack of investment in centres delivering allergy care," he insisted.

Also speaking at the symposium, Jennifer Feighan, CEO of the Irish Nutrition and Dietetic Institute (INDI), noted this is an area that is ‘often misunderstood'.

"For those who choose to self-diagnose there is the risk that an unrelated underlying problem could go undetected, or that major dietary adjustments are being made unnecessarily, which could lead to nutritional deficiencies if it is not managed properly," she explained.

She said that this is particularly worrying when it comes to children as good nutrition is so vital in the early years.

"It is important to raise awareness that if you are concerned about the possibility of a food allergy or intolerance you need to have it diagnosed accurately by a qualified professional, and it is equally important that dietary adjustments, especially those which impact on key food groups, are made in consultation with a registered dietitian," she added.

Meanwhile, also speaking at the event, Dr Marianne Walsh of the National Dairy Council (NDC), took the opportunity to explain the facts behind milk/dairy allergies and intolerances.

"Milk and dairy produce can be the subject of many myths. There are in fact two different types of food hypersensitivity associated with milk - cow's milk protein allergy and lactose intolerance. They are very distinct conditions," she noted.

She explained that cow's milk protein allergy results in a specific immune response to a protein, which is present in both raw and pasteurised milk.

"The allergy has a very low prevalence, affecting less than 3% of the population, mainly infants, but has a very good prognosis with 85-90% growing out of it by the age of three.

"Lactose intolerance is a condition that results from an inability to digest lactose, the natural sugar present in milk. The prevalence varies worldwide and by different ethnicities, but in Ireland and other European countries it only affects 4-5 % of the population. Most people with lactose intolerance can still tolerate consumption of a certain threshold of lactose each day," she said.

She emphasised that this highlights the need to consult with a registered, qualified professional ‘in order to establish what dietary changes should be made to manage a condition, rather than resorting to the risks associated with self-diagnosis and experimentation involving entire food groups, which are an important source of nutrition in the Irish diet'.

The symposium was organised for dietitians by the INDI and the NDC.