Can you tolerate these foods? More and more people can’t due to food allergies. On the occasion of Food Allergy Day, we reported last week on type I allergies. Today, we will devote our attention to type III allergies. These so-called delayed food allergies are becoming more common, and are more difficult to detect.
When diagnosing allergies, a distinction is made between type I and type III allergies. While these two allergies are mediated by the immune system, the antibodies involved are different. A type I allergy is mediated by IgE antibodies, and a type III allergy by IgG antibodies. About one to two percent of people suffer from type I allergies (immediate reaction), while approximately up to 40 percent of people are affected by a type III allergy.
Type III allergies are suspected to play a role in chronic bowel diseases, headaches, migraines and excess weight (Bentz et al. (Digestion 2010; 81:252–264), Uzunismail et al. (Gastroenterol 2012; 23 (1): 19–27), Guo et al. (The Journal of International Medical Research 2012; 0:204–210), Aydinlar (Headache 2013 Mar; 53(3):514–25), Alpay et al. (Cephalalgia 2010; 30 (7): 829–837)).
With a delayed food allergy, the symptom does not occur until hours or even days after the triggering food has been consumed. Due to this delayed reaction, it is often impossible to draw a discernible relationship between the symptom and a certain food. This makes detecting the cause of the complaints difficult. A blood test for IgG antibodies can offer certainty here. Once such results are known, it is essential to change one’s diet accordingly. In addition, provocation testing with the positive allergens should always be carried out before such a change in diet is adopted in order to confirm the IgG test result.
Foodscreen test for diagnosing type III allergies
A large amount of blood is no longer needed for an IgG antibody blood analysis. A small amount of capillary blood from the fingertip is sufficient for a reliable diagnosis. The following video shows how the dry blood sample is collected:
Advantages of allergy diagnostics using dried blood spot cards:
- Laypersons can take the blood sample, even from home. This means that the allergy test does not have to be performed in a doctor’s office.
- The blood sample does not have to be chilled and is stable for up to three weeks.
- The analysis is conducted in a certified laboratory.
- Dried blood samples do not have to be declared when they are shipped. The regulations for shipping biological material do not have to be followed.
- Unlike venous blood samples, a small sample amount is sufficient, which reduces stress for patients.
