Age and Allergy. DOES EVERYONE GROW OUT OF IT?
If you have a child with allergies, sooner or later some friend or relative will tell you not to worry
because your child ‘will probably grow out of it’. Your doctor may well say the same thing. But what
does this mean? Do all children shake off their allergic symptoms as they get older? If the symptoms
go, is the underlying disease completely cured? And why treat allergies if they disappear of their own
accord? The truth is that the relationship between allergy and age is incredibly complex, and doctors
only understand a tiny part of it. The best anyone can offer is a broad overview of how allergies
change with age, with few explanations of the underlying mechanisms, and absolutely no predictions of
what the future holds for any particular allergy sufferer.
It is certainly true that the classical allergic diseases, such as atopic eczema, hayfever and
childhood asthma (see box on p. 11), frequently disappear as children grow up. Babies tend to shrug off
food allergy and eczema by the time they are toddling, and a fair number of asthmatic children lose
their symptoms before they are ten years old, while others do so in their teens or early twenties.
Unfortunately, the disappearance of symptoms does not mean that the underlying disease has necessarily
disappeared, particularly in the case of asthma. Quite a few young adults find themselves wheezy and
breathless again in their late twenties or thirties, especially if they take up smoking. One study of
children who wheezed before the age of seven found that:
• 25% lost their asthma for a time – anything between two years and 25 years – only to get it
back again by their early thirties. Some recovered and relapsed more than once.
• Over 70% shook off asthma and were still symptom-free by their early thirties when the study
ended.
• Only 2% remained asthmatic throughout. Realistically, anyone who has ever been asthmatic should
regard themselves as ‘at risk’ indefinitely and never be careless with their health – don’t smoke, keep
away from smoky bars and clubs, eat a good diet with plenty of fruit and vegetables (206) and avoid
activities that involve an asthma risk, such as strenuous exercise in cold air.
Workplaces with high exposure to allergens, such as saw mills, bakeries or laboratories using animals
(see pp. 133-4) are not recommended for those with a history of allergy. Anyone who has ever had eczema
should also take care with cosmetics and soaps, choosing the gentlest brands. They should also protect
their hands (57) and avoid hairdressing or bricklaying as an occupation, or anything else where skin
irritation is likely.
Moving on
Growing out of classical allergies seems to be a consequence of the child’s immune system changing and
maturing as it grows. This same process, unfortunately, can also substitute one allergic disease for
another.
`When Alex developed eczema as a baby I hoped that she’d grow out of it in time. Well she did,
gradually, and by the time she was five it seemed to have cleared up, but then she started having a
snuffly nose that never really went away. A year or so later, she began wheezing whenever she got a
cold, and this has now developed into asthma.’ The pattern described by Alex’s mother Jenny will be
familiar to many parents, who watch their children slowly work their way through all the allergies in
the medical textbooks. Doctors call it the atopic march or allergic march.
Fortunately, even this type of allergic pattern can have a positive outcome eventually. Many such
children become allergy-free in time, and develop into healthy adults.
In the meantime, there are several itchy, wheezy or sneezy years to get through, and since childhood is
a time to be enjoyed, not endured, treatments that alleviate the symptoms of allergies are generally
welcomed. Being energetic, healthy, ‘normal’ and able to join in with sports and other activities is
particularly important for a child’s social development and self-confidence.
Treating the symptoms also prevents any long-term and irreversible damage, such as the thickening and
loss of elasticity that occurs in the airways of children with untreated asthma.
At the same time as treating the symptoms, it makes sense to maximise the chance of the child growing
out of the allergy. Parents can tip the odds in the right direction by providing an environment that
reduces the chance of new allergies developing. A detailed action programme is described on pp. 248-9.
Allergies that begin in adult life
What about those people who develop classical allergic diseases for the first time as adults - or even
in old age? Will they too ‘grow out of it’ with the passing years?
Only a minority of people develop such allergies for the first time as adults, although the numbers
seem to be increasing. The older you are when your allergies begin, the less likely you are ever to
throw them off. On the positive side, they are unlikely to get a great deal worse than they are at the
outset, especially if you take care of yourself and keep the air at home as unpolluted and
allergen-free as possible (see pp. 114-31).
In the case of asthma that develops in adulthood, there may not be an allergic reaction involved.
Whereas allergies play a part in asthma for 80-90% of children, the figure is thought to be lower for
adults. Nevertheless, it is well worth investigating the possible role of allergens, because avoiding
them is one of the most effective treatments.
The outlook for food intolerance
Food intolerance causes a wide variety of symptoms, from baby colic to migraine. A full list is given
on p. 76. Although far less is understood about food intolerance than about true allergies, there is
much more certainty about the future for affected individuals. With rare exceptions, people find that
the problem clears up as long as they totally avoid their problem food for a year or two. After this
period of strict avoidance, they can eat the food again in moderation but should never forget that the
problem can return. Eating the culprit food very regularly will turn the clock back and all the
original symptoms will return. This change for the worse may be irreversible for people with severe
reactions such as rheumatoid arthritis.
Safety first
Anyone who suffers the life-threatening allergic reaction known as anaphylactic shock (58) is probably
going
to have this for the rest of their days. Some children do become tolerant of food allergens in time
(allergies to milk, eggs or soya may well disappear, whereas fish or peanut allergy is probably going
to be permanent) but before concluding that there is no longer any risk, some extremely careful and
cautious testing should take place. Talk to your doctor about how to proceed. Skin-prick tests may be
helpful, but there must be resuscitation equipment close to hand as anaphylaxis can occur. Never give
the child any of the food to eat, until you (or, preferably, the doctor) have first tested it in other,
less risky, ways. For example, you can smear a little on the face to see if there is any reaction. If
there is none within 24 hours, put a tiny amount on the outer lip and watch again.
If both these tests produce absolutely no reaction then a very small amount of the food can be eaten as
a test: this should be done under medical supervision. The amount can be slowly increased with
successive tests, until it seems certain that no reaction will occur even with a normal portion.