Food Allergies and Intolerances – What Do You Need to Know About Them?

The notions of food allergy and food intolerance are often used interchangeably, but their definitions vary and are usually misused. So how do you distinguish allergies from food intolerances? What products can cause them? In the next series of articles on the blog I will try to clarify this topic. 🙂

Food hypersensitivity may be a common cause of gastrointestinal symptoms (e.g. heartburn, flatulence, nausea, feeling full after a meal), skin changes, or respiratory disorders (e.g. dyspnoea). Currently, it affects about 20% of the population, which is an important health problem worldwide.

Food hypersensitivity may be caused by the involvement of the immune system. In this case it is an allergy. All other reactions, not related to the immune mechanism, are called food intolerance.

 

 

Food Allergy 

Food allergy is a pathological reaction of the body to certain foods. IgE antibodies play the main part in the mechanism of its formation, therefore we can distinguish two types of food allergies:

• IgE-dependent,
• IgE-independent.

The first type is characterized by the occurrence of a rapid allergic reaction. These are the most common symptoms of the stomach, rhinitis, asthma, hives, joint pain, and even anaphylactic shock, which is especially dangerous as it can be life-threatening.

In the second type of allergy,  the reaction of the body to the allergen occurs later, e.g. inflammation of the small intestine, celiac disease or herpetic / atopic dermatitis.

Food allergies occur in approx. 6-8% of children under 4 years of age, 4% of adolescents and 2-3% of adults.

 

Food Intolerance

Food intolerance is defined as non-immune food hypersensitivity. General symptoms of food intolerance may include arthritis, asthma, gastritis, enteritis, irritable bowel syndrome, flatulence, constipation, diarrhea, migraine, sleep disturbances, chronic fatigue syndrome, itching, anxiety, depression.

Symptoms related to food intolerance appear relatively late after consuming a given product, from several hours to several days afterwards, therefore people usually don’t associate them with the food. 

The mechanisms leading to food intolerance are complex and not fully understood. However, it is assumed that it occurs when the body does not produce the enzyme necessary to digest a specific ingredient contained in a food product. An example is a person with lactose intolerance, whose body does not produce lactase, a substance responsible for breaking down sugars in milk and its products. 

Food intolerances can also be genetically determined or caused by chemical / pharmacological substances present in food products. They are usually added to preserve and process food (the so-called food additives).

It has been found that the most common reactions are caused by the following additives:

• Sodium benzoate (canned meat, fish, fruit, vegetables, ready-made meals, salad dressing, fizzy and fruit drinks) – asthma, hives, rash, rhinitis;
• sulphites (lettuce, shrimps, dried fruits and vegetables, orange juice, wine, beer) – nausea, vomiting, headaches, itchy skin, fainting;
• monosodium glutamate (Asian cuisine, instant soups, spices) – headache, weakness, palpitations, feeling anxious.

The above symptoms may be caused by consuming the product in large amounts and over a long period of time. In order to minimize them, it is necessary to read food labels, as well as observe your own body and recognize which specific products may cause undesirable effects. Remember that the less processed a product, the healthier it is.

 

 

Which Foods May Cause a Food Allergy and Which Lead to Food Intolerance?

Up to 160 different foods can trigger an allergic reaction. However, when considering the most allergenic foods, the so-called big eight include: cow’s milk, eggs, grains, soybeans, fish, seafood, nuts and peanuts.

Allergic disorders among some people are related to age and in the early years of life manifest themselves in the so-called “allergic march”, which is accompanied, inter alia, by food allergy and skin problems. Then, in adolescence, asthma and allergic rhinitis appear, which may persist into adulthood.

Most cases of IgE-dependent food allergy are acquired during the first two years of life. The cause of this phenomenon may be the immature intestinal barrier of the child, leading to a disturbed immune mechanism and imbalance of lymphocytes.

The most common allergenic foods in infants and children are cow’s milk and chicken eggs. They are responsible for up to 90% of allergic reactions at this age. At this point, it is worth mentioning that the use of an elimination diet by pregnant or lactating women is not a way to protect a child from allergies. At present, there is no scientific evidence that excluding potential allergens from the diet affects the development of an allergy in a child. Moreover, avoiding selected products may carry a risk of nutritional deficiencies and negatively affect the nutritional status of a woman.

In Poland, about 3% of children under the age of 3 are allergic to cow’s milk proteins. In children with this type of allergy, cross-reactions with meat products (e.g. veal, beef) are also sometimes diagnosed, therefore proper medical diagnosis is very important. These allergens are among the most allergenic among children. At the same time, it can be seen that a large percentage of children develop tolerance to cow’s milk allergens with age.

Egg allergy occurs in about 2% of children. A large proportion of them tolerate them better after thermal treatment (e.g. boiled, fried). As with an allergy to cows’ milk proteins, a large proportion of children grow out of this food allergy.

Wheat proteins are another allergen that causes reactions mainly in children over 3, but also among adults. It is the most common allergenic grain, but tolerance to it develops in 96% of adolescents under the age of 16.

 

 

In adults, the most common foods that cause allergies are nuts, fish and seafood.

Fish and seafood proteins are very strong allergens. Even a trace amount of them can trigger a dangerous reaction of the body, such as anaphylactic shock. These allergies occur in both children and adults, and studies show that acquiring tolerance is not common. This means that in most people this kind of allergy lasts for life. The prevalence of fish allergies ranges from 0-7%, and shellfish allergies from 0-10%, depending on the eating habits of the country.

The same applies to allergies to peanuts and other nuts. These types of allergic reactions occur in both adults and children, and growing out of them is very rare. Scientists have confirmed that peanuts are responsible for over 50% of allergies to nuts.

In the case of food intolerances, lactose intolerance is the most common in Poland and affects 1.5% of infants and children and 20-37% of adults.

In addition, you can also mention products containing: fructose (e.g. fruit, honey, glucose-fructose syrup) and histamine (e.g. tomatoes, smoked fish, long-ripened cheese, red wine).

 

 

There are many products that can cause an adverse reaction from the body. Remember not to cut out a large amount of products from your diet if you are in doubt about an allergenic ingredient, as your diet may become too poor in essential vitamins and minerals. In this case, it is best to see a specialist who will help you find the reason for your problems and choose the right diet.

 

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