Food Allergy and Allergic Rash in Your Child

What food allergy is

In general, an allergy is an immune response to certain agents, substances or particles that by their nature do no harm to the body.

But the body decides to attack them just as it would fight a bacterium or, for example, a coronavirus.

The same thing happens with food allergy — the body attacks foods that are usually important and good for people, such as milk and eggs.

Because diets in modern life are quite varied, and rashes and symptoms of poor digestion are with us fairly often, the question “Could this be an allergy?” is very relevant.

The main features of food allergy:

• It is a reaction to food that appears anywhere from seconds or minutes to 2 hours after eating the food, for immediate-type reactions, or within two days, for delayed-type reactions, which show up as gastrointestinal symptoms.
• It is an immune response in which antibodies to the food are produced.
• Even a small amount of food can trigger a serious reaction — anaphylaxis.

How common food allergy is

Food allergy is common among babies — under 1 year it is about 10%. But children often “grow out of” it, and over the years it becomes less relevant.

After 1 year the rate is 6–8%, and in adults — 5%. Severe food allergy can stay for life. Certain kinds of food allergy can also appear in adulthood, for example pollen-food syndrome.

Pollen-food syndrome, also known as oral allergy syndrome, is an allergic reaction that occurs in people with a pollen allergy after they eat raw fruits, vegetables or nuts.

This condition arises because of cross-reactivity between proteins found in pollen and similar proteins in foods.

Symptoms of food allergy

Food allergy usually shows up as:

• Rashes — usually in the form of acute hives (urticaria). This is redness of the skin, sometimes with paling in the center of the patches, which rise slightly above the level of the skin, vary in shape and size, and are usually very itchy. And yes, they look like skin stung by a nettle;
• Angioedema — swelling of the lips, eyelids, ear, fingers, and sometimes the tongue and throat;
• Itching, in particular of the ears and palms, and widespread redness of the skin.

In addition, there can be other symptoms:

• Symptoms in the digestive tract: nausea, vomiting, diarrhea, pain and cramps in the belly;
• Red, watery eyes;
• Breathing symptoms: runny-nose symptoms, wheezing, shortness of breath, tightness in the chest, hoarseness, coughing and sneezing;
• Paleness, a drop in blood pressure, loss of consciousness;
• Changes in your child’s behavior: anxiety, irritability, lethargy, seizures.

Food allergy in babies

Food allergy in babies needs particular attention.

This is the period when your baby meets a large number of foods for the first time, including the most significant food allergens.

At this age an allergy can be antibody-mediated — an immediate-type reaction — and show up with the symptoms listed above.

But babies often have an allergy that is not antibody-mediated, which can show up as atopic dermatitis and as symptoms in the digestive tract — food protein-induced enterocolitis, proctocolitis, esophagitis.

This kind of allergy shows up with vomiting, streaks of blood in the stool, excessive spitting up, colic and so on.

A baby who is formula feeding and not getting any solid foods can also develop a food allergy to formula.

After all, formula is made from animal milk, usually cow’s milk, and contains the corresponding allergen proteins.

In that case the doctor may recommend switching from regular formula to a hypoallergenic one with extensively hydrolyzed protein.

Soy formula is generally not recommended as a replacement option for cow’s milk protein allergy, since it cannot be considered hypoallergenic.

It is important to warn you not to make this decision on your own, because not every rash is a sign of allergy.

An allergy can develop even in a baby who is exclusively breastfed.

This is a very rare situation, which can happen in children with heightened sensitivity to food allergens, which, although in very small amounts, can still pass into the mother’s milk.

In that case the doctor may recommend that the mother eat the food in question in a threshold amount that does not cause a reaction.

Causes of food allergy

Allergy happens because of genetic predisposition – your baby inherits certain genes from their mother or father that “program” their immune system toward a tendency to allergy.

But environmental factors matter too:

• the environment
• the course of the pregnancy
• how long breastfeeding lasts
• the first contacts with food.

In particular, there is a dual exposure theory about allergens: children meet them both through the mucous membrane and through the skin.

So, if the contact with food happens mainly through the mucous membrane, that is through the mouth, the right kind of adaptation develops – tolerance.

If it happens through the skin, and especially atopic skin with a damaged barrier, allergy can develop.

In that case the body starts producing antibodies, immunoglobulins E, to food molecules.

Allergy can also develop through another mechanism – loss of tolerance.

How this works: a child, for example a child with atopic dermatitis that may or may not get worse from milk or eggs, has that food excluded for years.

According to statistics, one in five such children develops antibodies (immunoglobulins E) and an allergy to that food, and one in three develops an anaphylactic reaction.

Different studies show that IgE-mediated allergy to milk, eggs, wheat and soy usually resolves in childhood, while allergy to peanuts, tree nuts, fish and mollusks is usually persistent.

The danger of food allergy: should you exclude allergens

First and most important is the risk of anaphylaxis – an immediate severe reaction with a rash, swelling, shortness of breath, swelling of the throat or a drop in blood pressure and loss of consciousness.

Unfortunately, anaphylaxis can develop even to a very tiny amount of a food, start quickly, escalate rapidly and be life-threatening.

In this case it is very important to make the right diagnosis in time, to determine exactly what the allergen is, to assess the potential severity of the allergy and the possible risks.

Next, to determine the amount of the allergen the child can safely eat, and the form of cooking, for example baking, that will allow them to eat the food safely.

Why do all this, if you can simply get an allergen test and exclude all the dangerous foods?

This is very important.

If a food is well tolerated to a certain degree, or in a certain form, for example milk inside a baked muffin, it is very important to keep eating it.

And then, under a doctor’s supervision, gradually introduce a larger amount or less processed forms.

This is exactly the approach that will help prevent loss of tolerance and gradually build it for the future – the child will be able to eat the food.

Completely excluding an allergen food from a young child’s diet may seem like a simple solution.

But keep in mind that once your child starts going to a group childcare setting, school, summer camp or celebrations, the risk of meeting a potential danger will stay high.

Another danger is a deficiency of protein, vitamins and minerals when a child is on a restrictive diet.

Under no circumstances should you exclude the main sources of nutrients, such as milk and eggs, without adjusting the diet with a dietitian or nutritionist.

Otherwise a deficiency state is guaranteed.

And no less important a threat – your child may develop an eating behavior disorder.

This can be either because of a severe food reaction they have had – a fear of eating food – or because of strict dietary restrictions.

Diagnosing and treating food allergy

The main thing is that every case is individual, and in every case the key is careful diagnosis.

And you play a key role in this — your notes, a food diary recording when a reaction happened, what kind it was, and after which food.

In turn, the allergist carries out allergy tests: skin tests and blood tests, as well as an oral food challenge.

It is very important to interpret the test results correctly.

It happens, and quite often, that there is a positive result for food allergy while the food allergy itself may not be present at all.

That is because the presence of antibodies to a food in the blood does not yet mean that there is an allergy.

The doctor will always determine whether such a test is meaningful in each particular case, and whether there is a reaction to the food.

In the most severe and dangerous cases the food really does have to be excluded completely, when even the smallest amount (crumbs) can cause anaphylaxis.

In cases where a small amount of the food is well tolerated, it will be recommended to continue eating that amount or a particular cooked form.

This applies to the so-called ladders — the milk ladder and the egg ladder — when there is an allergy to milk or eggs. The food is introduced not only starting from a small amount, but also in a form that has undergone a high degree of cooking.

This is because, during baking, some allergens in these foods break down into small particles that have lost their allergenic potential. So they can be safely eaten.

Such allergens are found in milk, eggs, fruits and vegetables.

But these details are determined by the allergist using special, detailed allergy tests. Some foods contain allergens that do not lose their allergenicity at all during cooking. These include fish, seafood, peanut and tree nuts.

When fish or seafood is being cooked, even the vapors produced during frying or boiling can be dangerous. So if an allergy to these foods is known, it is important to avoid cooking them in the presence of the person who is allergic to them.

There is also a method of treating allergy used around the world — so-called allergy vaccination, or allergen-specific immunotherapy.

To carry out such treatment, doctors determine the minimum amount of the allergen that the child can receive without an allergic reaction. The child then receives this allergen every day, with the amount gradually increased.

This may be a measured amount of food — an amount of peanut flour is measured out, or an amount of baked muffin is weighed at home — or certain commercial products.

These may be tablets or powders, as well as skin patches containing a certain standard dose of the allergen.

In any case, the doctor provides an allergy action plan for a sudden accidental exposure and an immediate allergic reaction.

As a rule, in such situations a person with a food allergy is advised to stop eating immediately, call emergency services and carry an epinephrine (adrenaline) auto-injector pen.

This is a special syringe with a completely invisible needle, simple and quick to use, and a person needs a few seconds to give themselves the medicine. It is an immediate treatment, designed to be given not by a doctor but by parents, teachers or the patient themselves.

Allergens in solid foods: avoid or not

Solid foods are important both for nutrition and for development, and they are an important stage in the transition from breastfeeding, or formula, to eating at the shared family table.

The period of starting solids is a time of rapid growth and development, when babies are sensitive to a shortage or an excess of nutrients. Big changes in the diet also happen at this time, thanks to the introduction of new foods, tastes and feeding experiences.

There used to be a popular approach: allergens — and these were considered to be mainly fish, nuts, berries and fruit — the later, the safer.

But observation of children and large food allergy studies have shown that this is not the case.

First, the more common allergens are milk, eggs and other foods from the “Big Nine allergens.” And there is no reason to delay introducing these foods to a healthy baby!

Second, studies have confirmed that earlier introduction of egg and peanut into the diet, from 3-4 months, lowers the risk of allergy to them.

Of course, in the studies this early introduction took place under doctors’ supervision — so further on we will give comfortable and safe recommendations.

As for other foods, it is quite possible that the same mechanism works with them, but, as you know, the last word belongs to the evidence — so we are waiting for study results.

The main thing is that solid foods need to be introduced on time, without putting it off “for later,” even in children at increased risk of allergy, e.g. atopy in the child or the parents.

Atopy is an inherited tendency to develop allergic diseases.

Very often atopy is linked with atopic dermatitis. Although atopic dermatitis can indeed be linked with food allergy, in reality these two conditions occur together in only 1 in 10 children with atopic dermatitis.

That is why with atopic dermatitis a strict diet is completely unjustified. On the contrary, it is worth not missing the time for introducing allergens in solid foods, so that the child has time to develop tolerance to foods.

This supports proper growth, development and the timely formation of tolerance to foods. And only if an allergy does appear does such a child need an individual plan for introducing the allergen, worked out together with a doctor.

How to introduce allergens correctly

Usually parents try to avoid foods that often cause allergy, fearing reactions in their baby. In fact, these foods are key to a child’s successful transition from breastfeeding, or formula, to the family diet.

They include the so-called “Big Nine Allergens”:

• Milk and milk products
• Eggs and foods made from them
• Cereals containing gluten — wheat, rye, barley, and products made from them
• Soy and soy products
• Fish and fish products
• Seafood — mollusks, crustaceans, and products made from them
• Peanut and peanut products
• Tree nuts and products made from them
• Sesame and its derivatives

In addition, there are other foods that have a certain allergenic potential, so concerns can arise about them too.

These include celery and other foods that are extremely important in a child’s diet: fruit, berries, fresh vegetables and legumes.

Is there a schedule for introducing allergens

First of all, healthy babies and babies with signs of atopy are advised to start solid foods at 4-6 months, guided by signs of readiness.

This also applies to the main allergens mentioned above.

It is important to include in your baby’s diet all the foods the family usually eats, apart from those not allowed at their age. It is also worth introducing your child to foods they will come into contact with later as they grow: daycare, school, children’s parties and so on.

This will help maintain tolerance to these foods.

It is also worth noting that the absence of a reaction to infant formula cannot completely rule out a milk allergy. That is why babies who are formula-fed or mixed-fed need to be introduced to dairy products taking into account their allergenic potential.

As for a schedule for introducing allergens into solid foods, there are currently no categorical recommendations about the order in which foods are introduced, or the number of new foods that can be introduced in one day.

And one more fact – today there is no rule about a gap between introducing new foods.

The most important thing is that foods should be rich in fats, proteins, carbohydrates, iron, zinc and other important micronutrients.

So the diet should be varied and include all food groups, namely:

• Grains, roots and tubers.
• Legumes and nuts.
• Dairy products (milk, yogurt, cheese).
• Eggs.
• Meat, fish, poultry, liver and other animal-source foods.
• Vegetables and fruits rich in vitamin A (yellow and orange).
• Other fruits, vegetables, berries and greens.

However, if you need more specific guidance, you can rely on the following general advice on introducing the allergens from the “big nine”:

• Start with a small amount of the food (for example, 1/8 tsp) and, if there are no allergic reactions, gradually increase the portion over the next few meals.
• To make it easier to track reactions to a particular food, introduce only one new allergen per meal. It is best to do this in the first half of the day, so you have enough time to watch for possible allergic reactions during the day.
• If your child has a mild or moderate allergic reaction, postpone introducing this allergen and give your child an antihistamine according to the instructions. In case of anaphylaxis – an immediate, severe reaction – call emergency medical services.

Be sure to consult an allergist about diagnosis and further treatment.

• To maintain tolerance, foods that have not caused reactions should be included regularly in your child’s diet. This applies to all foods, and a varied diet will help with this.

You can also use these tips if you are planning to add such rare but allergenic foods as lupin, or mustard as a natural spice, to the diet. For example, if you eat them often or these foods are widespread in your area.

Allergen labeling: what consumers need to know

Under the law, Ukraine has a list of 14 main allergens, similar to the one used in EU countries.

These allergens must be clearly stated on the label of food products and in menus at food outlets if they are part of the product or dish, even in small amounts or in a modified form.

All potential allergens are set in bold or underlined in the text so that consumers can easily notice them.

Such requirements are aimed at protecting consumers’ health, in particular those who have allergies or food intolerance, and they oblige manufacturers to provide accurate information on product packaging.

This helps consumers choose foods safely and avoid potentially dangerous substances.

The list of 14 main foods that cause allergic reactions or intolerance:

1. Milk and dairy products
2. Eggs
3. Fish
4. Mollusks
5. Crustaceans
6. Soy
7. Cereals containing gluten – wheat, rye, barley
8. Tree nuts
9. Peanuts
10. Mustard
11. Sesame
12. Celery
13. Lupin
14. Sulfur dioxide and sulfites

Conclusion

Food allergy is common, and it is especially relevant in childhood.

Food allergy has a major impact on the quality of life of the whole family, imposing significant dietary restrictions, constant worry and fear of a severe anaphylactic reaction to food. All of this can lead to nutrient deficiencies and eating disorders.

That is why seeing a doctor promptly, getting an accurate diagnosis and following the right treatment plan are extremely important.

Sources:

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