BROAD BEAN ALLERGY
Key Allergens
Broad beans (also known as faba or fava beans) are in the
Fabaceae family of plants, these are also known as legumes. Other plants in this family include kidney beans, peanuts, peas, lentils, lupin, green beans and soya beans. If you want to find out more about legumes you can visit the
Legume page.
Broad beans contain
7S seed storage proteins and
11S seed storage proteins, much like most other legumes. These proteins aren't always broken down by cooking or processing and can cause severe allergic reactions.
Broad beans contain chemical compounds called vicine and convicine which in certain people with an enzyme deficiency can cause favism, a condition which affects red blood cells and can cause serious anaemia.
Food Intolerances
Broad beans are high in histamine when they are eaten from cans, this is because of the ways they are preserved. Canned beans are not suitable for people who are following a low histamine diet.
Broad beans are a high FODMAP food. FODMAP stands for
Fermentable
oligosaccharides,
disaccharides,
monosaccharides
and
polyols. Foods high in FODMAPs can cause symptoms of food intolerance, affecting the gastro intestinal system and this can be mistaken for a true IgE food allergy.
Broad beans are a food high in
salicylates. Salicylates have the potential to cause worsening of asthma, swelling, itching and hives as well as food intolerance symptoms in people who are sensitive to salicylates.
Broad beans contain large amounts of
lectins, another cause of food intolerance. Cooking foods with lectins makes them more digestible and can reduce the symptoms of food intolerance.
You can read more about
Food Intolerances on the dedicated Food Intolerance Page.
Associated Syndromes
Broad beans can cause what seems to be a severe allergic reaction in some people, but is actually a condition called Favism. Favism is only seen in people who have a Glucose-6-Phosphate Dehydrogenase (G6PD) deficiency. The lack of this enzyme can cause red blood cells to deteriorate, causing symptoms like jaundice, shortness of breath and dark urine.
This is an X-Chromosome linked disorder, so disproportionately affects males as they only need 1 defective X chromosome to be affected by this condition. It can be found in women, but they would need 2 defective X chromosomes, one from each parent.
Cross Reactivity
Other foods containing 7S seed storage proteins include peanut, pecan, hazelnut, soya bean, walnut, lupin, sesame, adzuki bean, black eyed pea, black gram, buckwheat, cashew, chia seed, chickpea, coconut, fenugreek, garbanzo beans, lentils, macadamia, mung bean, palm oil, pine nut, pistachio, quinoa and red bean.
Foods containing 11S seed storage proteins include almond, cashew nut, kiwi, mustard, sesame, soya and walnuts.
Visit the
Legumes page if you react to all types of legumes and would like a more extensive list.
These food lists are not exhaustive, the most up to date information is available on the Cross Reactivity Tool.
Resources
Websites
Science Direct - Vicia faba
Histamine Foods
Healthline - FODMAP foods
ATP Science - Salicylate Foods
Science Direct - Favism
Rare Disease Database - Glucose-6-Phosphate Dehydrogenase Deficiency
Articles and Journals
Shotgun proteomics and in silico analysis of potential allergens in mature seeds and sprouts of purple winged bean, 2024
Co-sensitization between legumes is frequently seen, but variable and not always clinically relevant, 2023
11S globulin identified as a new bean allergen, 2023
Lentil allergens identification and quantification: An update from omics perspective, 2022
Nutritional management of immediate hypersensitivity to legumes in vegetarians, 2022
Contribution to the estimation of the prevalence of food allergy in schoolchildren in the city of Guelma (Algeria), 2021
Lectin Activity in Commonly Consumed Plant-Based Foods: Calling for Method Harmonization and Risk Assessment, 2021
Dietary Lectins: Gastrointestinal and Immune Effects, 2020
Identification and Quantification of Major Faba Bean Seed Proteins, 2020
Hypersensitivity linked to exposure of broad bean protein(s) in allergic patients and BALB/c mice, 2014
Modulation of IgE immunoreactivity to broad bean proteins after food processing in a Moroccan population, 2014
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