Allergies

Allergies are becoming much more common. In some areas, over 30% of 13 and 14 years olds complain of asthma, and 40% of hay fever, and health services struggle to keep up. is the answer a crash programme to training new allergists, or are the simpler and cheaper solutions, perhaps involving food?

An allergy is a hypersensitivity of the immune system to a foreign substance, such as pollen, house dust or particular foods, which are harmless to non-allergic people.

The over-reactive immune system treats these normally harmless substances as invaders, going into emergency mode with the well-known allergic responses of wheezing (asthma), running nose, allergic rhinitis or hay-fever, and skin problems (aczema, urticaria or nettle rash), and in extreme cases, anaphylactic, shock - a very dangerous, potentially fatal, condition.

Some people have a much greater tendency to these reactions than others and their condition is known as atopy. most cases of atopy involve many factors, including foods, but the term 'food allergy' is also used very widely for all sorts of reactions to foods, many of which are not allergies at all. For these the term food sensitivity is better.

Both true food allergies and other food sensitivities are much more common now than than they were twenty of thirty years ago. This is especially so with nut allergy, particularly peanut allergy, where a potentially fatal reaction to this normally harmless nut can occur within minutes. Unfortunately, such severe reactions are very much less rare than they were.

Why is this so? Many people now have unstable immune systems which overreact, like a burglar alarm set to call the police when burglars enter but which in fact, goes off when a spider walks past. Instead of producing a few drops of fluid to flush out some pollen grains, these over-reactive immune systems produce a torrent of hay-fever of a severe attack of wheezing.

Research is needed to find out why so many people's immune systems are so jumpy. Theories range from immune-system overload due to the vast number of foreign chemicals to which we are exposed now, to immune-system under-activity, due to our over-hygienic environment. Another possible cause is that immunization programmes have wiped out the childhood illnesses that helped to build healthy immune responses in the past. Probably all these factors play a part, but the fact is that we do not really know.

Although we do not fully understand food allergies and sensitivities, we do know that improving general health, lifestyle and environment can greatly diminish, if not actually completely cure, many of these problems.