People with a banana allergy may be more likely to be allergic to other substances, such as latex.
A banana allergy, similarly to all allergies, occurs when the immune system overreacts to something that is otherwise harmless.
The symptoms of different allergies vary from person to person and from allergen to allergen. Some people might show only mild skin irritation while others can experience the life-threatening reaction called anaphylaxis.
People who have a banana allergy are more vulnerable to allergies to other substances as well as bananas. There are two reasons for this.
Firstly, an allergy is a sign of an over-reactive immune system that may also react to other substances that appear harmless.
Secondly, the proteins in bananas are similar to proteins in some other natural substances, notably latex, which is used in things such as hygiene gloves, balloons, and condoms.
Banana allergies are relatively uncommon and do not rank among the most common allergies. In most areas of the world, less than 1 percent of the population has a banana allergy. However, people with allergies to substances that contain proteins similar to those in bananas are at a heightened risk.
A person is more likely to have a banana allergy if they are allergic to other fruits and vegetables or latex.
Other risk factors for banana allergies, as well as for allergies to other foods, include:
- a history of eczema or atopic dermatitis
- an allergy to anything else, including foods, pollen, and plants
- a history of oral allergy syndrome with any foods
- having asthma
- a family history of allergies, especially to bananas
The symptoms of banana allergies depend on the type of allergy a person has. Symptoms can also change over time.
A relatively minor allergy, called oral allergy syndrome (OAS), occurs when the banana comes into contact with the skin of the lips, mouth, and throat.
The symptoms of OAS may include swelling of the mouth or throat.
OAS is due to the presence of protein in a fruit or other plant material that is similar to that found in pollen. OAS is often worse during allergy season.
The symptoms of OAS include:
- a rash or sores on the mouth, lips, or tongue
- swelling of parts of the mouth or throat
- in rare cases, anaphylaxis
Symptoms of OAS tend to appear immediately after a banana is eaten. Other forms of banana allergy can also cause anaphylaxis and usually appear immediately following banana consumption.
Also, some people experience gastrointestinal distress and babies may have painful diaper rash. Adults can have sores on and around the rectum when proteins from the digested banana have come into contact with the skin.
Some people, especially young children and infants, develop a red rash after eating bananas and other acidic fruits. This is not a true allergy but a skin irritation from the acidic fruit. Wiping the mouth and face immediately after eating can reduce or eliminate symptoms of irritation.
Banana allergy in infants
Symptoms of a banana allergy are similar in infants as they are for anyone else.
A person should always be cautious when introducing new foods to an infant, particularly to common allergens such as peanuts. If a child has eczema or another allergy, the risk of a severe allergic reaction to a food or other substance is greater.
It is still recommended to introduce common food allergens, however, including peanuts, tree nuts, soy, and eggs, to an infant when they are between 5 ½ and 7 ½ months old. Delaying the introduction of these foods increases the risk of food allergies.
Parents and guardians should monitor infants and young children for signs of an allergic syndrome called food protein-induced enterocolitis syndrome (FPIES).
Many babies and children with FPIES initially show signs of allergies to breast milk or formula. FPIES then usually causes allergies to many foods when these start to be eaten, though dairy and soy are among the most common triggers.
Children with this disorder often need to eat a limited diet, and untreated FPIES can cause severe malnourishment and dehydration.
Other foods to avoid
Banana proteins are very similar to proteins found in many other fruits and vegetables. So, if someone has a banana allergy, it is important for them to consider allergy testing to know what foods they can and cannot eat safely.
A cross-reaction to banana is also seen in those who are allergic to ragweed, especially during ragweed pollen season in the late summer and fall.
As well as banana, some foods a person with a banana allergy might need to avoid include:
- bell pepper
People with a banana allergy are also likely to develop an allergy to latex, which is used in many common products, including hygiene gloves, balloons, and some condoms.
Anyone who has concerns should tell a doctor about any history of banana allergies before using latex products and consider testing for a latex allergy.
Many people are still able to eat cooked bananas if they have a banana allergy. This is because the allergen protein disintegrates when the banana is cooked. It may not be necessary to avoid cooked foods containing bananas, but only an allergist can provide someone with accurate, individualized information about the risks.
When to call a doctor
Irritation and rashes may not always be caused by a banana allergy, so it is important to report these symptoms to a medical professional if they cause concern.
Banana allergies are often treatable, but not all rashes and signs of irritation are due to allergies. This means that allergy testing can help determine what the right treatment is, as well as rule out other potential health conditions.
A person should report signs of an allergic reaction to a doctor who may refer them to an allergist if necessary.
Infants who experience a rash after eating a banana may be at risk of anaphylaxis. A parent or caregiver should call a doctor immediately when babies or very young children show any signs of an allergic reaction.
Difficulty breathing, swelling of the throat, loss of consciousness, and other serious allergy symptoms are potentially life-threatening emergencies, so a person should call 911 or their local emergency number. A doctor may prescribe someone with an epinephrine injection pen (EpiPen) to reduce the risk from dangerous symptoms in the future.
More than a quarter of children outgrow their allergies, so it is possible that a child with a banana allergy may eventually be able to eat bananas safely.
Children who have only mild allergic reactions are significantly more likely to outgrow the allergy. However, no research has specifically studied people outgrowing allergies to bananas.
Banana allergies can be inconvenient, but bananas are easy to avoid. People should not, however, assume that their banana allergies are harmless or will go away with time. Even a minor banana allergy can develop to be more severe or cause a serious reaction.