Nurture Article | The Portland Hospital Parenting Magazine
Winter Issue 2011 | Sophie Goodchild
Dealing with runny noses, coughs and rashes is an everyday reality for parents, especially those with children under 10.
For some though, there is more behind these common childhood complaints than just a virus. Your child could be suffering from an undiagnosed allergy. According to the charity Allergy UK, an estimated 45 per cent of children and babies now has an allergy – and the rate is increasing.
Dust mites and cats – or ‘inhalant’ allergies – are the most common triggers in small children, and, as they get older, this can lead to pollen allergies. Babies start with eczema and then progress to asthma and finally hay fever and rhinitis. While there is some evidence that the upwards surge in eczema and asthma cases is levelling off, Asthma UK says this country still has one of the highest rates of asthma in the world.
Food allergies to cow’s milk, egg white and wheat are also regularly diagnosed in infants and toddlers.
Dr George Du Toit, a consultant in children’s allergies at The Portland Hospital, says most young children outgrow allergies by the age of three. However, the concern is that doctors are seeing more children suffering from multiple food allergies. Peanut allergy is on the rise with one in every 70 children in the UK now affected.
Tree nuts, particularly cashew, can also trigger a reaction as well as sesame, particularly in concentrated forms such as hummus and tahini. “It’s now rare that a child is allergic to just one food,” says Dr Du Toit. “So where a single food allergy is established one should always look for additional food allergies such as kiwi, fruit, fish, shellfish and soy.”
While the exact cause of this allergy ‘epidemic’ is unclear, major studies are being carried out in the UK to answer this question. Some experts blame sedentary life-styles, where children spend their time indoors playing computer games and TV.
The US Environmental Protection Agency recently suggested that indoor air quality – which can contain millions of pollutants such as dust and chemical cleaners – may have a more damaging effect on health than outside air. Poor ventilation is also to blame, especially double glazing which ‘traps’ pollutants and air conditioning which pushes dirt and chemicals into the air inside our homes.
Other experts, including Dr Adrian Morris from the Surrey Allergy Clinic in London’s Harley Street, favour the ‘hygiene hypothesis’; that children are over-protected from dirt and bugs in early infancy so there is no bacteria for the immune system to attack, so instead it switches to being hyper-vigilant against allergies.
“Current research suggests that infants should sleep with the family cat and be fed peanut butter from birth, as high-dose allergen exposure early in life appears to switch off allergies in infants under one year of age,” says Dr Morris. “Once allergies become established in toddlers, then this ‘switching off’ will no longer occur.”
Modern diets of ‘exotic’ foods including nuts and fruits – which are relatively new to the Western diet – are to blame for triggering allergies in older children, believes Dr Morris. For example, kiwi fruit and lychees contain a potent allergy-triggering protein called profilin.
Although harmless, profilin can produce a severe allergic reaction in some children. “I‘m amazed at the number of children fed avocado, hummus and Nutella, while parents withhold pasta and dairy products for fear of provoking allergies,” says Dr Morris. Establishing if a child really does have an allergy – or is just a cranky eater – can be a challenge. A key warning sign, says Dr Du Toit, is if a child has a severe reaction soon after eating certain foods.
Cold symptoms which don’t go away when an infant is exposed to dust or pets are another sign. Your genes also play a part – if you suffer from hay fever then your children are at a higher risk of developing allergies.
However, some children only display mild allergy symptoms which can make diagnosis difficult, says Dr Du Toit. “With respect to food allergies, if the reaction is severe such as wheezing, coughing, swelling, vomiting or gut pain soon after ingesting a food then it’s usually obvious, unless the allergen is hidden in a processed food,” he says.
“It’s harder to diagnose a food allergy if the symptoms are mild.” For example, when a baby is being weaned from breast to cow’s milk, they can develop an allergy to the cow’s milk which initially they tolerate.
Symptoms may simply be a change in sleeping patterns at night, colic, back arching and signs of pain, which could be attributed to other things.
“In these situations, it may take some skill to diagnose an allergy,” adds Dr Du Toit.
Before doctors can diagnose an allergy, they have to find out what is causing it. A competent GP or allergy clinic can do this using a skin prick test, where a few drops of allergen are gently ‘pricked’ into the surface of the forearm with a small needle.
If a child is allergic, the skin will swell over the next 15 to 20 minutes. A blood test – called the Radioallergosorbent (RAST) test – is another method. This measures levels of specific antibodies in the blood and is accurate for children aged 4 months upward.
The positive news is that many children do eventually grow out of their allergies, especially food-related ones. Eczema and asthma also tend to improve as the child gets older. “Inhalant allergies tend to persist, but about half of all eczema and asthma will settle in puberty,” says Dr Morris.
WHAT IS AN ALLERGY?
One in four of us will develop an allergy at some point in our lives. From dust to tree pollen, everyday substances can trigger an ‘abnormal’ reaction in some people. Their bodies go into overdrive by producing too much of a special antibody called Immunoglobulin. This triggers other blood cells to release chemicals including histamine and the result is an allergic reaction.
For more information on allergy trials visit