By Caroline Hutto, CNM, ARNP
As the rebirth of summer is almost upon us, spring brings the glory of allergy season. Seasonal allergies are an extremely common occurrence. The pollen that is essential for plants to reproduce and live again is small enough and can get far enough into our nose and lungs that the immune system signals an attack to the foreign invaders. This attack signals white blood cells to enter tissues creating inflammation and swelling of our nose and sinuses. The inflammatory signals that usually help discourage unwanted bacteria go into overdrive creating the itchy eyes, running nose and increased mucus secretion showing up as the symptoms we know today as seasonal allergies. Birch, alder, grass and ragweed allergies are extremely common allergens across North America and usually the most likely culprits for allergy symptoms, but there are others that can cause havoc as well.
Unfortunately, when the pollen activates the immune response, it has the potential to cross react to other plants, fruits and vegetables. The immune system, when it ‘sees’ a foreign body like pollen, it does so by touch. The white blood cells touch with their receptors and if the molecule is not like parts of the body, it declares war starting the signaling cascade calling other white blood cells to the battle. This usually works well for viruses or bacteria, but for pollen it’s an unfortunate case of mistaken deadly foe. Once activated, the white blood cells are on constant guard looking for any foreign invaders trying to sneak by. Since they are only able to see by touch, other plant matter can be marked as part of the evil pollen scheme to invade and a reaction to a food or plant, that has no relation to the pollen, can start. This is called a cross reaction.
When allergy season strikes there are certain foods that have the potential to cross react with certain pollen; they are close enough in molecular characteristics to confuse an already activated immune system. When a cross reaction occurs, eating these foods can increase the allergy symptoms making things worse. Additionally, if the body has other conditions, such as inflammatory bowel disease, cross reacted foods during allergy season can create irritation and flare ups that dissipate when allergy season is over and the overactive immune system has moved from war to peace. This can also be true for those with allergies who experience issues with leaky gut leading to a decreased feeling in overall health.
Below are a list of foods that can cross react to pollen taken from the American Academy of Allergy Asthma and Immunology.
This list is not extensive and other foods can create symptoms that aren’t on this list, just as all foods that are on this list may not cause cross reactivity but have the potential too. It depends on the immune system and how it sees the plant matter. Sometimes it’s a case of the immune system being there in the right place at the right time to start a cross reaction. At the very least, if allergy season is the worst, maybe this can make it a little better.