Food Allergies And Intolerances: All On The Subject

According to figures from the National Food Safety Agency (ANSES), food intolerances and allergies have doubled over the past five years while becoming disabling. Almost 8% of children and around 4% of adults have to watch everything they put on their plate. But why this spectacular growth? How to recognize the symptoms of a food allergy and prevent them? What are the foods most often involved? Who are the people most affected? Is there a suitable treatment that allows you to go shopping quietly? Deavita.fr takes stock of the subject for you!

Everything you need to know about food allergies and intolerances

What exactly is a food allergy? It is indeed an abnormal reaction of the immune system triggered by specific foods. This reaction occurs either suddenly, within 2-3 hours after ingestion of food, or delayed, 48 hours later. Immunity reacts adversely to these foods by overproducing immunoglobulins, usually type E.

What are the symptoms ?

Usually the symptoms are mild (tingling of the lips or rash). But sometimes the allergy can become serious and even fatal. In this case, identifying and banishing the offending foods is a must. In France, between 50 and 80 people die each year from a food allergy. Here are the most frequently reported symptoms to know:

• skin symptoms, such as itching, rash, hives, eczema, lip pruritus, atopic dermatitis (especially in infants), lip edema, tingling of the lips or mouth, angioedema.
• gastrointestinal symptoms, such as abdominal pain, nausea, vomiting, diarrhea, colic, gastroesophageal reflux disease.
• respiratory disorders, such as asthma, rhino-conjunctivitis, rhinitis.
• generalized reactions, such as drop in blood pressure, malaise, anaphylactic shock

Generally, allergic reactions can cause one or more of the symptoms listed. And as already mentioned, they appear from a few minutes to a few hours after ingestion of the food. They can vary depending on the sensitivity of the person.

The causes of food allergies and their rapid growth

Almost all food allergies fall under the category of type I allergic reactions. Depending on the allergen, the allergy can develop in early childhood or during adolescence. It can appear at too fragile age and disappear in adulthood or persist throughout life. The different possible scenarios are many and they are all studied to explain the origin of the increase in the occurrence of food allergies in the world population. Here are some of the more well-known causes:

• imported foods vary and diversify our diets while exposing us to several allergenic products.
• air pollution dramatically decreases immunity
• technological manipulations in the food industry increase the occurrence of food allergies and intolerances
• decreased breastfeeding of infants is increasingly common
• specific hygiene in children preventing the proper development of their system
• immune system can also be the cause of a food allergy
• early consumption of certain foods, or overconsumption of others during childhood
• genetic predispositions to food allergies

Besides the listed causes, the environment, too, plays a very important role in the occurrence of allergies.

And to explain the impressive increase in allergic reactions in recent years, scientists put forward several reasons, including breastfeeding which has declined considerably. Believe it or not, there are many studies attributing anti-allergenic properties to breast milk. Furthermore, the dietary diversification of infants has become too early.

According to a Finnish study, the introduction of 4 foods before the age of 4 months would multiply by 3 the risk of eczema, while only milk is essential before the age of 6 months. The evolution of the food industry and the many ready-made meals rich in potential allergens, additives of a protein nature such as egg white, milk powder, casein, lupine flour, can also increase the various reactions of severe allergies.

What are the allergenic foods to avoid?

Normally, the most allergenic foods are not the same from one country to another. They may vary depending on the typical foods of the region. In Asian countries, for example, rice allergy dominates, while in Scandinavian countries, fish allergy is more common. In Europe, among the most allergenic foods, we find:

• the peanuts
• nuts (almonds, Brazil nuts, cashews, hazelnuts or filberts, macadamia nuts,
• pecans, pine nuts, pistachios, walnuts)
• cow's milk
• eggs
• the fish
• seafood (crab, lobster and shrimp)
• soy
• wheat, rye, barley, oats, spelled, kamut and cereal-based products (gluten)
• sesame seeds

Note: in newborns, allergy to cow's milk is the one that occurs most frequently before the introduction of solid foods. This is the case for about 2.5% of babies.

Screening: food allergy or intolerance?

It is not always too easy to find the food to which you are allergic, especially when there are cross allergies. It is important to perform a test to find out which foods are problematic, especially in children. The diagnosis is usually made by a food allergist, who performs a food survey and immunological tests (skin, blood and provocation). If the person then presents one or more of the symptoms mentioned following ingestion of the same food, the food allergy is the cause.

However, food intolerances, which are generally of metabolic origin or due to the ingestion of a large amount of foods rich in tyramine or histamine, should not be confused with allergies. Although they have similar symptoms, they are completely different! And it is thanks to immunological tests that we can distinguish between intolerance and allergy.

What is cross food allergy?

Cross-food allergies are usually due to a similar immunohistochemical structure between two allergenic foods. In other words, the antibodies synthesized against the first allergen recognize the second allergen because of their structure too close. Among the most common cross allergies are:

• food-to-food allergies (nuts and almonds, lupine and peanuts, kiwi and mustard, cow's milk and beef)
• food-pollen allergies (fruits / vegetables and birch or peach and cypress)
• food-latex allergies (kiwi / avocado / banana / chestnut / melon and latex)

What treatment to relieve allergies?

Although several studies are underway for the development of immunotherapy treatments for allergen desensitization, to date there is unfortunately no effective treatment for the different types of allergies. Faced with a food allergy, the main treatment remains that based on the exclusion of food or foods containing allergenic substances. Also, as with all other allergies, there are effective ways to relieve symptoms.

Once the food allergy has been confirmed by an allergist, the only effective treatment remains eviction. What does it consist of? To remove allergenic foods from their menu. However, foreclosure can be problematic, especially if you have a cross allergy or allergy to eggs (found in many products and foods). It is therefore necessary to read the labels of each food purchased very carefully. In the event of meals taken outside, do not hesitate to ask questions of the restaurant owner or the chef. And in addition to the food advice of the allergist, you can also opt for the services of a dietitian in order to obtain an adapted diet and avoid the deficiency, due to the elimination of a type of food.

As for other ways of relieving allergic symptoms, they depend on the symptoms. We therefore find the following treatments:

• H1 antihistamines are usually prescribed systemically to relieve symptoms of hives, rhinitis, or allergic conjunctivitis
• intestinal transit retarders are used to relieve gastrointestinal symptoms, such as diarrhea, vomiting, nausea
• in case of eczema-food allergy, specialists prescribe emollient and moisturizing creams
• in case of asthma, a basic treatment is required (thermal cures are also possible, but must be prescribed by a doctor)
• adrenaline auto-injectors, on the other hand, represent an emergency treatment to be used in case of anaphylactic shock

Whatever your symptoms, no treatment is possible without a medical consultation. Avoid self-medication! Otherwise, you risk causing unwanted side effects.