B.Sc. N.D. Dip Hom. Dip Nutrn. (AUS)
I believe that around 40% of the Hong Kong population should be classified as allergic. In 2001, the University of Hong Kong surveyed 4,448 children aged between 6 and 7 years and found that 37.4% of them had suffered from allergic rhinitis in the 12 months prior to the interview. A 1995 survey found that 35.1% of the children had symptoms.
This allergy is most often attributed to the increase in air pollution or a family history of wheezing and respiratory tract infections. While I agree that many allergic rhinitis cases relate to pollution, most allergies are caused by a sensitivity to house dust mites or foods, with dairy being the most common offender.
Allergies can cause just about any symptom in adults, but in children the list of common complaints is shorter.
In infants, allergies are normally the cause of a colicky baby who is restless, cries frequently, sleeps poorly, and has digestive troubles like reflux, diarrhoea, and gas or colic.
In older children, the common physical signs are dark rings and lines under the eyes, a frequently running nose, breathing through the mouth, and recurring coughs and colds and/or recurring earaches. Eczema, dermatitis, and other itching skin complaints form the other most common group of symptoms for allergic children.
Symptoms can vary over time. For example, if your child had colic as an infant, recurring tonsillitis and earaches as a toddler, frequent coughs or asthma bouts as a child, and digestive problems or migraines as a teenager, the cause for all these symptoms could well be an allergy to a food or other substance.
A few of the more unusual complaints that can be caused by childhood allergies are bed-wetting, recurring nausea and vomiting, nose bleeds, and croup.
Sometimes symptoms only affect the mind. Allergies can commonly cause hyperactivity and mood swings, difficulties concentrating in school, ADD and/or ADHD, insomnia, or restless sleep.
Case History Examples
A child's bed-wetting was resolved after avoiding orange juice, a common irritant causing this complaint. Another common trigger food for bed-wetting is tomato products.
In another case, I treated a four year-old boy with a three-year history of recurring upper respiratory tract complaints. His mother reported that his nose was always dribbling clear mucous, he had colds monthly, and had several bouts of otitis (earaches) in the first two years. Now his head colds mostly moved into his chest. Antibiotics provided only minor relief as the condition recurred quickly afterwards.
I was alert to the possibility of a dairy allergy causing all these problems, which was confirmed. The results of a dairy-free diet were striking. Within 10 days, his nose cleared completely, the first time since he was a baby. As an added bonus, his sleep and digestion suddenly improved too. After three months he had not had another chesty cough, only a simple viral head cold from which he recovered in a few days.
The parents of these two children had no idea that an allergy could have such a powerful and pronounced impact on a child's health. Like many parents, they thought food allergies would cause rashes or asthma and did not link their child's symptoms with food allergies.
Types of Allergic Reactions
The Classic (IgE) Allergic Reaction. This is an immediate reaction, usually of the nose (with sneezing) or skin (redness). Only 5% of all food reactions fall into this category. This is the type of allergy that can be diagnosed with a skin prick test or a blood test for IgE antibodies. Most people can work out these allergies for themselves as the reaction to the substance occurs very soon after contact with the offending substance; for example, sneezing after contact with hay pollen or house dust.
Peanuts, strawberries, citrus, eggs, and shellfish are common food examples. Common symptoms include hives, asthma, rhinitis, hay fever, eczema, anaphylactic shock, and fatigue. This type of classic allergic reaction is usually treated with antihistamines, which treat the symptoms but not the cause. I prefer homeopathic treatments as these can often cure the problem through desensitisation.
Hidden (IgG) Allergic Reaction, or delayed food intolerance reactions. This type of allergy involves another immunoglobulin, usually IgG and sometimes IgA or IgM. IgG make up 75% of all antibodies and are produced by the B-lymphocytes. They cause hidden allergies, sometimes called food intolerances, with masked or delayed reactions. It can take hours or even days after eating the food before you notice a reaction, which makes it much harder to find the offending food.
Over-exposure to any substance, even to those that don't give us an initial bad reaction, can give rise to an eventual addiction to that substance. This is felt as a withdrawal reaction a day or two after the food is removed, such that the person seeks the food to relieve the withdrawal symptom. In short, the food is craved. Offending foods causing the delayed food intolerance are usually caused by foods we eat every day such as wheat, milk, sugar, and yeast.
Causes, Prevention, and Treatment of Allergy Sensitivity
There is a strong genetic component to allergic sensitivities, as half of the children born to allergic parents are also allergic. Children who are not breast-fed also have a higher risk of allergy, as do premature babies.
Another common cause of food intolerance and allergy reactions is antibiotic treatment. In one study, asthma and hay fever symptoms were increased significantly in the group where antibiotics were given to children under one year. More than four courses increased the chance of asthma 402% in a follow-up of children 5 to 10 years old. One or two courses increased the chance of asthma/hay fever by 227% over the children who had not been given antibiotic doses.
Antibiotics remove the friendly bacterial flora from the intestines, which in itself may cause allergies. To add insult to injury a yeast infection called Candida (or thrush) may establish itself in the intestine of persons with a lack of good intestinal flora, and the yeast further increases the development of allergies (e.g., to yeasts and sugars). Although some consider Candida a fad diagnosis, it is quite easy to conduct a stool test and identify abnormal levels of Candida. Sufferers usually have a lot of gas, bloating, and mood swings. In the case of children, it is often the cause of eczema and poor immunity.
Studies have shown that allergy rates can be reduced in children. One way is for the breast-feeding mother or infants under one year to take supplemental Lactobacillus (a helpful bacteria for the bowel). This supplement has reduced allergy rates by 50 per cent in one study.
Another allergy prevention method is to delay the introduction of allergy provoking-foods to infants. Egg, oranges, peanuts, and, some would say, wheat are better introduced after the first year, as by this age the child's digestion is more developed.
In a similar way, reducing house dust exposure in the child's bedroom with careful cleaning, washing fluffy toys, and using an air filter reduces dust allergy development.
At IMI, we see plenty of adults with these insidious allergy conditions as well as children. The pace of life in Hong Kong and environmental factors can play havoc with allergies. People who never believed that they are allergic can suddenly find themselves feeling a general sense of malaise they can't quite seem to shake.
The first step in treating of an allergy is to identify the triggering foods. Allergy testing at IMI is a simple and painless procedure. After identifying the triggers, they can be easily removed. Although it can be a stressful process at first, the rewards are lasting and often profound. For some parents they feel like they have a new child when the allergies are removed, and for many adults, they feel like they have a new lease on life as well as improved immunity.