Detecting the specific food that causes unwanted symptoms can be extremely difficult. Although food sensitivity is an increasingly common topic in nutrition practice, it still remains insufficiently researched in science. Currently, no sensitivity test can definitively diagnose sensitivity to a particular food.
The difference between sensitivity, intolerance and allergy
Food sensitivity:
Definition: An immune reaction led by immunoglobulins G (IgG), M (IgM) and A (IgA).
Symptoms: Gas, diarrhea, abdominal pain, joint pain, migraines.
Food allergy:
Definition: A strong immune response to food caused by increased production of
immunoglobulin E (IgE) antibodies.
Symptoms: They appear immediately or within 2 hours and include a rash, redness, swelling of the tongue,
difficulty swallowing or dizziness.
Food intolerance:
Definition: It occurs when the body lacks the enzymes to digest certain foods.
It has nothing to do with the immune system and is not life-threatening.
Symptoms: It can cause gastrointestinal problems.
Food Sensitivity Tests
Many tests measure the amount of antibodies as the immune system’s response to a particular food,
including IgG and IgG4 in the blood after exposure to a food allergen. However, research shows
that many of these tests are not reliable, because many other factors, including different antibodies and
cellular reactions, may be involved in food sensitivity.
Some tests claim they can determine sensitivity based on genetic analysis, but this is still not
sufficiently researched or reliable.
Allergy Tests
Skin allergy test:
Description: It involves pricking the skin with a needle containing a small amount of allergen and observing the
reaction. Negative tests are reliable, while positive ones indicate the possibility of an allergy.
Use: It is used to confirm an allergy based on the history of symptoms, the reaction,
an elimination diet and a food diary.
Blood test:
Description: Measuring the amount of antibodies in the serum in relation to a specific food allergen.
Use: It may show a higher level of antibodies to a particular food allergen, but the food
does not necessarily cause clinical allergy symptoms. It is used only for confirmation based on
a food diary, an elimination diet and the history of symptoms.
Elimination Diet
An elimination diet is the best way to diagnose and treat food allergy and intolerance.
This approach involves eliminating one or two foods from the diet for 2-8 weeks in
every form (raw, cooked, frozen), and then reintroducing them.
Eliminating several foods at once can harm an individual’s nutritional status. By systematically
reintroducing foods, one by one, reactions are carefully observed. If there are
symptoms/complaints even after eliminating the suspected food, there are other causes. If the
symptoms subside and the skin allergy test is positive, that food should be excluded from the diet
until an oral allergy test is done for additional confirmation of the allergy.
Oral food test:
Description: It is done when the symptoms subside after eliminating the food, without taking
antihistamine medications. Foods are checked one by one, on different days, with
careful observation of symptoms.
Food diary
Keeping a food diary is a key tool in identifying problems with food. The diary should be
kept for 3-7 days, with a detailed description of food intake for breakfast, lunch, dinner and snacks, the time
of intake, the amount of food, feelings after the meal, gastrointestinal or other complaints, the time symptoms
appear and the composition of the dish.
Understanding and identifying food sensitivities, intolerances and allergies requires a careful and
systematic approach. An elimination diet, keeping a food diary and consulting an expert
are key steps toward improving your health and wellbeing. If you suspect problems with
certain foods, turn to your nutritionist or doctor for further advice and proper
guidance through the process of diagnosis and treatment.
Jovana Arsović
professional nutritionist-dietitian