Strawberry allergies can be annoying, and even dangerous, to those who are severely allergic. Interestingly, the allergy originates in the vibrant red color of the fruit.
How the allergy is triggered
Strawberries contain different kinds of proteins, and some trigger allergies in humans. The human immune system will mistakenly identify the proteins as harmful and initiate an allergic response. Even if you are allergic to strawberries, your first exposure may not produce an allergic response, but your body’s immune system is reacting by producing immunoglobulin E (IgE) antibodies in preparation for the next exposure. The second time you have strawberries, if you are allergic, the IgE antibodies will stimulate mast cells to produce histamine. The histamine creates blood vessel dilation, fluid secretion and muscle spasm to varying degrees. No one is sure why some people have these allergies and others don’t, or why some people have mild reactions while others may have life-threatening episodes.
Researchers from the University of Lund in Sweden have isolated a particular protein which may trigger the allergic reaction. This is the protein which gives the strawberry is color; it is not found in white strawberries. The protein is similar to the one in birch pollen which triggers allergic responses. If you have a birch pollen allergy, you may also be allergic to strawberries.
Signs of a strawberry allergy
Swelling of the tongue or mouth, itchiness, rashes, hives, watery eyes, vomiting, diarrhea, and in extreme cases, anaphylactic shock are the common symptoms for strawberry allergy. Strawberry allergies can be identified through the common scratch test by an allergist. Blood tests for the allergy will also verify it.
Avoidance is the best strategy
The best way to handle a strawberry allergy is to avoid it. Even processed and cooked strawberries carry the allergy-inducing protein, so stay away from spreads, jams and baked goods containing strawberries. Watch for multi-berry desserts and yogurts which may contain strawberries but don’t mention them by name. If you really enjoy strawberries, look for the white varieties – they are hard to find and can be expensive, but they are safe to eat.