Dr. Robert Pastore, PhD, CNS

Food Allergy

#071 - On Pollen Food Allergy Syndrome

Dr. Pastore continues on the topic of food allergies, and how many are connected to pollen and seasonal allergies (better known as “hay fever”).

2020-07-2410 min read

The Pastore Podcast
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SHOW NOTES

How common are pollen allergies? [0:40]

  • American College of Asthma Allergy and Immunology reports 25 million Americans suffer from seasonal allergic rhinoconjunctivitis (SAR) also known as seasonal allergies, hay fever, particularly in childhood and adolescence
    • Primarily sinus-related - runny nose, nasal congestion, sneezing
    • Water eyes
  • 1 of every 6 Canadians suffer from seasonal allergic rhinoconjunctivitis


Be careful with Benydryl for seasonal allergies [1:50]

  • Over the counter medication is an acetylcholine interrupter
    • Decreases acetylcholine - important neurotransmitter for motor neuron responsiveness and memory
    • Slows reaction time
    • Difficulty remembering names/words
  • Speak with your doctor about the type of allergy medication that is best for you


Pollen Food Allergy Syndrome [3:20]

  • Last week covered that food allergies can be linked to other medical conditions, either caused or made worse by consuming the allergic food
  • Pollen Food Allergy Syndrome can be difficult to find/diagnose
  • Condition tied to classic pollen allergies
  • Pollen food allergy syndrome is a common adverse reaction occurring a few minutes after the consumption of specific pollen-related foods in patients with pollen-induced seasonal allergic rhinoconjunctivitis (SAR)
    • Occurs in people who are already proven sensitive to pollen / have seasonal allergies
    • Pollen food allergy syndrome often has oral/pharyngeal symptom
      • Itchy tongue/throat/mouth
      • Sinuses & watery eyes
      • Can be any set of symptoms above the neck (head, eyes, ears, nose, throat)
      • Skin rashes & hives
      • Nausea & vomiting in more severe cases
      • In rare cases, anaphylaxis

The pathogenesis of pollen food allergy syndrome [5:45]

  • Pathogenesis = development of medical condition or disease
  • Linked to respiratory allergy to pollens and cross-reactivity between pollens and plant derived protein
    • Respiratory allergy to pollen (inhale the pollen) & plant-derived proteins from a related fruit or vegetable that has similar impact on the immune system akin to the pollen
  • Called a homologous epitopes
    • Homologous = having the same relation, relative position, or structure
    • Epitope = part of the antigen that the immune system recognizes
    • Homologous epitopes = similar parts of the antigen that is recognized by the immune system
    • Similar parts of the allergen (antigen) are recognized in both the pollen and the food
      • Antigen = substance that you are reacting to, stimulates an immune response to attack the “threat”
      • Antibody = produced by immune system (B-cells) to target a substance your immune system reacts to
        • Will tag an antigen
        • Creating an antigen-antibody complex
        • Which signals other immune cells to attack the threat
        • Can create mast-cell histamine response
        • Causes all symptoms of an allergy

  • Foods you eat to nourish yourself could be making your seasonal allergy symptoms worse, because you’re allergic to those foods too

There is a difference between a histamine mast-cell response, and a true IgE immune system response

  • First contact via the respiratory tract to pollen allergens that leads to the allergen sensitization process and development of allergic rhinitis
    • You breathe in pollen, get allergy symptoms
  • After that exposure and immune reaction a second step transpires wherein plant-derived foods that contain cross-antigens to the inhaled allergens
    • Your immune system is responding to the pollen exposure
    • You introduce a fruit that shares the similar allergen epitopes
      • Example: birch pollen allergy, eat kiwis - allergy
      • Stimulates second immune system response
  • Causes a secondary immune response via t cells and IgE memory
  • Resulting in a food allergy reaction
  • Pollen allergy crosses over to food allergy, both symptoms for both worse
    • Need to track down both allergies
  • Food allergy can show up at any time
    • If more allergenic food proteins appear to show the same epitopes, the IgE antibodies cross-react, binding to the food component causing an antibody antigen reaction without any prior history of contact allergen

How many people that have pollen allergies have Pollen Food Allergy Syndrome? [11:30]

  • Most data from children & pediatric population
  • 42.7% of children in Korea who had pollen allergies had Pollen Food Allergy Syndrome
  • 31% of children in Sweden
  • 12% in Mexico
  • 29% in Italy
  • 29.7% in Croatia
  • Under 12.9% in UK & Australia
    • Likely underreporting
    • Allergists prescribe immune system suppressors to shut off immune system response, can give false negatives
  • 1 of 3 people with SAR/hay fever in USA & Canada - reaction is caused by an immune system food response


  • Travelling outside of country, exposure to new foods/pollens can cause allergy response


Why is Pollen Food Allergy Syndrome so under-diagnosed? [16:30]

  • Allergists typically focuses on external environment
  • Often give medication without testing patients
  • Won’t look for it unless patient brings up suspected reactions themselves


Cross-reactions can be tested via elimination diet [18:50]

  • Write down frequency of suspected foods (see list below)
  • Eat each of the foods one at a time without another food
  • Wait 4 days to determine reaction
  • Record allergy symptoms - flare/same/better/worse/
  • Repeat with other suspected foods on the list
  • Bring suspected list to doctor for scratch test, regional allergen test & IgE blood test


Pollens and Triggering Foods [21:10]

  • List is growing & highly dependant on geographical location, foods consumed and the travel of an individual
  • Look at regional environment & surrounding state environmental allergens of all places you reside (vacation homes, extended travel)
    • Regional Environmental Allergy Panel IgE
    • Molds, pollen, grasses, trees

  • These fruits, vegetables, nuts, legumes & seeds species share a similar epitope to the pollen of the plant/grass/tree [23:30]
    • Specific similar antigen stimulation of our immune system
      • Structure of proteins in the foods are almost identical to the environmental pollen allergen
    • Multiple areas of structural similarity
      • Component in amino acid structure called a beta sheet
        • Example - Alzheimer's patients produce harmful proteins - beta amyloid plaques - structure
      • Profilins sequences can be 75% similar in the food & the pollen
        • Close enough for immune system to see both as a threat
      • Lipid transfer proteins
        • LTPs can bind to molecules & travel across membranes
        • Shared between both pollen & food
        • Ex - Dr. Pastore’s wife  - itchy mouth eating banana, secondary reaction to latex due to allergic LTP association. Share same LTP immune system reaction

  • Alder Pollen - apple, cherry, peach, pear, parsley, celery, almond, hazelnut

  • Birch Pollen - kiwi, apple, pear, plum, apricot, cherry, tomato, celery, carrot, fennel, potato, green pepper, cumin, pear, hazelnut, walnut, almond, peanut, lentils

  • Cypress/Cedar - peach, citrus fruit, apple, melon, tomato

  • Grass - melon, watermelon, orange, tomato, kiwi, potato, swiss chard, peanuts

  • Mugwort - peach, lychee, mango, grape, celery, carrot, parsley, fennel, garlic, cabbage, broccoli, coriander, cumin, sunflower seeds, peanuts

  • Pellitory - peach, cherry, melon, pistachio

  • Ragweed - watermelon, banana, zucchini, cucumber, squash


  • Identify the source, stop the primary immune system response, may not react or have seasonal allergy symptoms anymore

Diagnostic process for Pollen Food Allergy Syndrome [32:00]

  • Walk into your allergist’s office prepared
    • Write down frequency of consumption of suspected foods (see list below)
    • Eat each of the foods one at a time without another food
    • Wait 4 days to determine reaction
    • Record allergy symptoms - flare/same/better/worse/
    • Repeat with other suspected foods on the list
    • Bring suspected list to doctor for scratch test, regional allergen test & IgE blood test
  • Request that your physician or allergist run the following:
    • Skin prick test for full list of foods associated with the pollen
    • Total IgE (to rule out false-negatives)
    • Regional Environmental Allergy Panel IgE
    • IgE panel for full list of foods associated with the pollen
  • Once tested, complete an oral food challenge (elimination diet) when allergy symptoms are present, allergy is clear, but test negative IgE
    • Stop eating that food, determine how you feel
    • If the history & symptoms are clear, you may be reacting in a different (non-IgE) way
    • Reintroduce at a later date & assess symptoms
      • Keep food fresh/raw when trying
      • Heating can affect some of the immune system reactions
      • Makes the reaction more mild, but still a reaction

What is the treatment for Pollen Food Allergy Syndrome? [38:00]

  • Strict avoidance of triggering foods
    • Sadly on 53% of cases that allergists recommend this, rely on medication more
    • 9% did not mention food restrictions at all
  • Individual patient advice
  • Absence makes the immune system grow fonder
    • Remove cross-triggering foods, difficult to avoid the environmental pollen when living in the area
    • Identify other non-allergy immunological food reactions
  • Identifying true food allergies can result in a normalization of blood pressure [43:00]
  • The solution to pollution is dilution

Environmental pollen allergen + food allergen occurring at the same time creates dramatic water retention & pulmonary (lung) issues

  • Difficult to breath, exercise is difficult
  • Reduction in cardiovascular output
  • Gut issues in pollen/food allergies too
  • Different types of pollen & grasses, severity based on the season

Can you eat the food allergen if the pollen allergen is not in season? [46:00]

  • Immune system reaction will still be present, just not as severe
  • If the related food is continually consumed, even after pollen goes out of season, can still form IgE allergy (more severe) rather than a mast-cell histamine reaction
    • Due to immune system IgE memory
    • No pollen in the winter, no symptoms from pollen allergy, but still reacts to the food
  • Stop the exposure, immune system can calm down, IgE memory may “forget” and the food won’t stimulate the immune system any more


Wrap Up [52:00]

  • Be an advocate for your own health
  • Record your symptoms, gather as much data as possible
  • Talk to your family about pollen & food allergies
  • Share this information with your doctor
  • www.drrobertpastore.com
  • help@poweronpoweroff.com
  • @drrobertpastore



LINKS

Top 9 Food Allergy Podcast

https://drrobertpastore.com/podcasts/070-food-allergies

University of Manchester Foods Cross-Reacting with pollen: http://research.bmh.manchester.ac.uk/foodallergens/facts/pollen/pollenandfood/

Pollens and Triggering Foods

  • Alder Pollen - apple, cherry, peach, pear, parsley, celery, almond, hazelnut
  • Birch Pollen - kiwi, apple, pear, plum, apricot, cherry, tomato, celery, carrot, fennel, potato, green pepper, cumin, pear, hazelnut, walnut, almond, peanut, lentils
  • Cypress/Cedar - peach, citrus fruit, apple, melon, tomato
  • Grass - melon, watermelon, orange, tomato, kiwi, potato, swiss chard peanuts
  • Mugwort - peach, lychee, mango, grape celery, carrot, parsley, fennel, garlic,
  • cabbage, broccoli, coriander, cumin sunflower seeds, peanuts
  • Pellitory - peach, cherry, melon, pistachio
  • Ragweed - watermelon, banana zucchini, cucumber, squash

Speak to your doctor regarding:

  • Regional Environmental Allergy Panel IgE

  • A skin prick test
    • Stimulates to see if there is a histamine response
  • A total IgE
    • To ensure you have enough IgE to test for
    • If your body is not producing enough IgE, can lead to false negatives
    • Total IgE = how much IgE you produce at any given time, you should be producing some
    • Cutoff is 187, if less than 5 means you may be IgE deficient

  • IgE food allergy blood test against specific foods
    • IgE panel should be aggressive as possible, as many foods & environmental allergens as possible
    • Definitely run for the top 9 & any other suspected foods

  • If something was flagged, practice an elimination diet for at least two weeks
    • Then, if symptoms are not as severe as anaphylaxis, in the presence of your physician attempt an oral food challenging
      • Eating the suspected allergen to see if it causes a direct response
    • NOT appropriate for everyone, but is definitely helpful in revealing cause and effect