Food allergies

# What are food allergies? Around 4-5% of the population are affected by food allergies. The immune system reacts to normally harmless proteins in food and regards them as foreign bodies. Typical triggers are nuts and pulses, hen's eggs, cow's milk, soy, wheat, pome and stone fruit, celery, carrots, fish, seafood and meat. Allergies to nuts, cow's milk, soy, wheat and hen's eggs are most common in children. Adults are usually allergic to nuts, soy, celery or seafood. Most of those affected react to one to three different foods. The most important treatment is to avoid the food in question. In children with a milk protein, wheat or soy allergy, the symptoms often subside after a few years, as the body learns to tolerate the allergens. If an allergy occurs for the first time in adulthood, it is usually permanent - such as an allergy to fish or seafood. Nut allergies also often persist for longer or permanently. The causes of food allergies are complex and are based on an interplay between genetic make-up and the environment. It is assumed that 80% of the risk of a food allergy is determined by hereditary factors. > ## Allergy versus intolerance > > An allergy is an overreaction of the immune system to a protein component of a food. This includes allergies to nuts, soy, fish, wheat, cow's milk, etc. > An intolerance, on the other hand, either lacks an enzyme that is important for the digestion of a food or a transport protein for absorption. These include lactose, fructose and histamine intolerance or gluten intolerance. > Both forms have different symptoms, courses and treatment approaches. # What does it mean to suffer from a food allergy? A food allergy means that the immune system reacts to certain proteins in foods that are normally harmless. This can lead to unpleasant and sometimes dangerous symptoms, such as skin rashes, nausea, abdominal pain, shortness of breath and even allergic shock. Food allergies can occur at any age and can have serious consequences if not treated properly. It is important that people with food allergies are aware of and avoid the allergens that may trigger adverse reactions in them. Allergic shock can be life-threatening, so it is advisable that those affected learn how to recognize this reaction and act quickly. > ## Good to know > > The allergens in some foods, such as certain vegetables or fruit, change when heated and do not cause allergic reactions when cooked (compote, puree, jam...). > Herbs can also be tolerated when dried. # What does genetics have to do with it? We are investigating four genes with regard to your tendency to food allergies: The HLA system (human leukocyte antigen system) is a group of genes that carry the blueprint for proteins of the same name. The group includes numerous genes and their subgroups such as HLA-A, HLA-B, HLA-C, HLA-DR, HLA-DRA, HLA-DQ, HLA-DP and many more. The corresponding proteins play a central role in the immune system. Some variants of these HLA proteins are associated with different forms of allergy. - Variant rs7192 of the HLA-DRA gene: The genotypes G/T and T/T generally show an increased risk of food allergies, especially for a terminal nut allergy. - Variant rs9275596 of the HLA-DQ gene: The genotypes C/T and C/C generally show an increased risk of food allergies, especially for a terminal nut allergy. The C/C genotype carries a slightly higher risk compared to the C/T genotype. The T/T genotype does not show an increased risk. The SERPINB7 gene (serpin family B member 7 gene) carries the blueprint in the cells for the two inflammatory proteins interleukin 4 (IL-4) and interleukin 13 (IL-13), which are involved in allergic reactions. - Variant rs12964116 of the SERPINB7 gene: The genotypes A/G and G/G show an increased risk of food allergies, with G/G carrying a higher risk compared to A/G. The A/A genotype shows no risk. The IL-4 gene (interleukin-4 gene) carries the blueprint for the messenger substance interleukin-4 in the cells. This protein can reduce inflammatory processes and prevents overreactions of the immune system. - Variant rs11949166 of the IL-4 gene: The genotypes A/T and T/T show an increased risk of food allergies, with T/T carrying a higher risk compared to A/T. The genotype A/A shows no risk. The A/A genotype shows no risk. The HRNR gene (Hornerin gene) carries the blueprint for the protein of the same name in the cells, which is involved in building the skin and mucous membrane barrier, among other things. Variants of the gene are associated with an increased tendency to allergies. - Variant rs2155219 of the HRNR gene: The genotypes G/T and T/T show an increased risk of food allergies, with T/T carrying a higher risk compared to G/T. The G/G genotype shows no risk. - Variant rs12123821 of the HRNR gene: The genotypes C/T and T/T show an increased risk for food allergies, with T/T carrying a higher risk compared to C/T. The genotype C/C shows no risk. The genotype C/C shows no risk.