An estimated 0.1 – 1.2% of the population experience allergies to banana, but it is most often seen in conjunction with allergies to other foods, either presenting as Pollen-Food Allergy Syndrome (Pollen Food Syndrome) or Latex Food Syndrome.
Pollen-Food Allergy Syndrome (PFAS) occurs in some hayfever sufferers who are already allergic to certain tree pollens, most commonly birch, alder, and hazel pollens. Protein structures in these pollens are similar in shape to those present in plant foods and certain nuts so that allergy symptoms start to occur when those foods are eaten. This is due to cross reactivity.
Latex Food Syndrome is also caused by cross reactivity due to protein shape. In these cases, there is a similarity between the proteins in latex and those in banana. It is estimated that 45% of people with a latex allergy are also allergic to bananas.
With PFAS you would likely see minimal allergic reactions limited to the swelling and itching of lips, mouth, and tongue, so although an unpleasant experience you would not need to carry an epi-pen.
With Latex Food Syndrome sufferers may experience more severe symptoms including generalised urticaria, abdominal pain, vomiting and anaphylaxis.
You may also encounter contact allergic reactions from touching the fruit itself or the peel of the banana, which is thought to be due to the protein chitinase.
Look out for labels…
Avoidance of bananas is ideal, especially for those suffering from the more extreme allergy symptoms.
Watch out for
- Fruit salads, fruit drinks and smoothies and anywhere else where banana might be an unexpected ingredient
- Prescription medicines sometimes contain banana flavouring hasn’t been added
- Shampoos, conditioners, lip balms and body lotions, especially those with ‘natural ingredients’, always be sure to read ingredient lists
Symptoms from the milder Pollen-Food Allergy Syndrome will subside on their own with time, but an antihistamine will ease the symptoms more quickly.
There are not currently any immunotherapy treatments widely available for the lesser known allergies, so the only treatment remains avoidance of triggers and management of symptoms.
45% of latex allergy sufferers are also allergic to bananas. This cross reactivity is thought to be due to chitinase which is found in the rubber tree and bananas. Chitinase is a plant derived enzyme which is made by the plant naturally to act as a defence against fungal attacks.
Some of the linked allergies are in foods which contain high levels of chitinase, like chestnuts, kiwi, avocados, papaya, and tomatoes.
Other linked allergies linked to banana are
- Birch Pollen
Plantain is a relative of the banana, but I couldn’t find enough information about plantain allergy. It could be that they don’t contain the same allergens (or levels of allergens) as bananas or that plantain is cooked before eating, denaturing any proteins that may illicit and allergic reaction.
For those with suffering with Pollen-Food Allergy Syndrome or Latex Food Syndrome there is plenty of evidence that once cooked or heated banana can be eaten because the protein that causes the reaction is deactivated by heat.
This is a blog and should not be used for advice on diagnosis or treatments.
If you think you may have a food allergy, please contact your GP in the first instance to discuss treatment options.