If you are allergic to a pollen you may be allergic or react to certain foods such as apples, celery, nuts, melons or bananas. Numerous studies have confirmed the reports of people who have pollen allergies reacting to certain foods. The most well described and studied of the food-pollen syndromes is the oral allergy syndrome (OAS) or as it is also called “the burning mouth syndrome” because of the typical reaction noted by affected people. After eating a food that cross reacts with a pollen to which you are allergic, burning or tingling sensations begin in your mouth. Itching, pain, swelling and difficulty swallowing or breathing may occur. True anaphylaxis resulting in total body collapse from shock and death if not reversed has rarely been reported.
Typical pollen allergy symptoms such as runny nose and congestion, itchy watery eyes, and wheezing are also commonly reported. Other symptoms described include nausea, stomachaches, headaches, diarrhea and chest or throat tightness. Very few people are aware of these associations. Most doctors, except a few allergists and gastroenterologists, do not explore patients allergy history in the context of possible food reactions. Educating people about these types of conditions is one of the primary goals of “the food doc”, Dr. Scot Lewey, a practicing gastroenterologist (stomach-intestine specialist).
Ragweed pollen has been shown to be associated with these type of reactions after people eat bananas and fruits in the gourd family such as watermelon, honeydew, and cantaloupe. Pollen from Mugwort, another weed also known as Sagebrush, in the Artemisia family, has been associated with allergic reactions to celery, carrots, fruits in the Rosaceae family (apples, cherries, peaches) and those in the Gourd family (melons). Pistachio, persimmon, peanuts, almonds, sunflower seeds, hazelnuts, lettuce, camomile tea, and honey have also been reported to cause reactions in some people who are Mugwort pollen allergic.
Birch tree pollen is associated with numerous food cross reactions including celery. Cross-reactivity between celery and Birch pollen occurs more in central Europe whereas in Southern Europe celery and Mugwort reactions are more common. A Mugwort-Birch-Celery-Spice syndrome has also been described. People allergic to both Birch tree and Mugwort weed pollen may react to spices like pepper and paprika in addition to celery, carrot, and mango. Birch pollen is strongly associated with food reactions to Rosaceae family fruits (apples, apricots, peaches, pears, cherries), tree nuts (walnut, hazelnut, Brazil nut), legumes (peanut, various beans and peas), members of the Parsnip family (parsnip, parsley, anise, cumin, caraway, coriander) and the potato-nightshades (potato, tomato, peppers).
House dust mite, a serious allergen for many people, cross reacts with mangos, shellfish, bananas, melons, tomato, avocado, papaya, pineapple, peaches, Kiwi fruit and various spices. Kiwi, an unusual fruit in a class by itself, may elicit a reaction in people allergic to Birch trees, Mugwort weed pollen, and latex. The Latex-Fruit Allergy Syndrome is characterized by allergy to foods in the Rosaceae family including almond (classified as a fruit not a nut) and plums, as well as other fruits such as passion fruit, papaya, pineapple, mango, melons, and bananas. It is also associated with reactions to spices such as dill, ginger, and oregano and the nightshades, potato and tomato and chestnuts.
A few articles in scientific literature have reported associations of specific HLA gene patterns to pollen allergy and fewer still have noted HLA DR and DQ gene pattern associations with food-pollen cross-reaction syndromes. HLA DQ genetics are well known in celiac disease. There is also limited published data associating certain DQ patterns with microscopic colitis, collagenous colitis and non-celiac gluten sensitivity. HLA typing may be clinically useful in evaluation and elimination diet recommendations for suspected food allergic, intolerant or sensitive individuals. This type of information will be one of the goals of thefooddoc.com website. A table that lists the common pollens and foods that have been reported to cross-react with those pollens will be posted on the site very soon.
Though extensive research has been done and many of the protein structures contributing to these cross-reactions is known, little is known about these reactions by most of the lay public and many doctors. Seasonal pollen allergies may be associated with more severe reactions. Those with documented cross-reactions or prior OAS reactions may be at increased risk and certain HLA gene or DQ patterns may be associated. People with known or suspected pollen allergies should be aware of these possible food reactions. If you would like further help sorting out if you are intolerant or allergic to certain foods please visit http://www.thefooddoc.com in the near future to undergo a free online assessment and sign up for the online diet symptom diary, updates, and access the free educational content.