10 Signs you’ve developed a food allergy as an adult

Adults can also acquire food allergies, which frequently take people off guard. Food allergies are not simply a problem for children. 

In this in-depth study, we explore the realm of adult-onset food allergies, illuminating the warning signs, symptoms and difficulties that individuals who are affected must deal with. 

Adult food allergies are becoming more common, therefore it’s critical for those who want to preserve their health and wellbeing to be aware of this issue.

Adults may navigate their food choices more skillfully, avoid probable allergens, and reduce the risk of life-threatening allergic responses by identifying the symptoms and getting a prompt diagnosis. 

Join us as we expose the untold stories of food allergies that develop as adults and provide you with knowledge for a safer and healthier future.

What are food allergies?

When the body misinterprets particular food proteins as dangerous intruders, it can lead to immune system responses called food allergies

Contrary to food intolerances, which often include digestive issues, food allergies result in various symptoms that can impact several bodily systems. An abnormal immune reaction to particular food proteins is a food allergy. 

The immune system of a person with a food allergy misinterprets the proteins in the triggering meal as dangerous and generates substances like histamine to combat the mistaken threat. This immunological reaction causes various symptoms that can be moderate to severe.

how food allergies develop
Photograph: wirestock/Envato

How food allergies develop

Even if you’ve previously eaten the item without experiencing any problems, food allergies can arise at any age. 

The immune system develops hypersensitive to a specific dietary protein through frequent exposure or in reaction to an environmental trigger. 

Immunoglobulin E (IgE), a kind of particular antibody produced by the immune system during sensitization, is intended to target and combat the perceived threat [1]. 

IgE antibodies alert the immune system to release chemicals when the allergenic food is subsequently consumed, leading to an allergic response.

Common allergenic foods

All meals have the potential to trigger an allergic reaction, but certain foods are more likely to do so than others. The most typical food allergies are as follows:

  • Tree nuts like almonds, walnuts, and cashews and peanuts
  • Shellfish (such as lobster, crab and shrimp)
  • Fish
  • Eggs
  • Milk
  • Soy
  • Wheat
  • Several fruits, including kiwi, citrus fruits and strawberries

What are the symptoms of food allergies?

Understanding the signs of a food allergy is essential for early diagnosis and effective therapy. Food allergy symptoms can appear in a variety of ways and may have an impact on numerous bodily systems.

Physical symptoms

Food allergies can cause physical symptoms that might range in severity and appearance. The following bodily signs might manifest in a person with a food allergy after ingesting the offending food:

  • Itchy or tingling sensation in the mouth, lips or throat
  • Swelling of the lips, tongue, throat, or face (angioedema)
  • Hives or raised, red, itchy bumps on the skin (urticaria)
  • Abdominal pain, cramps or vomiting
  • Diarrhea or loose stools

Gastrointestinal symptoms

After ingesting the allergenic food, people could experience nausea or a queasy feeling in their stomach.

After consuming the trigger meal, some people may have recurrent vomiting episodes. An increase in bowel motions brought on by eating the allergic food might cause loose stools or diarrhea [2].

The stomach area may experience pain or cramps, which can be uncomfortable and can result in a bloated or swollen feeling.

Itching can be localized or generalized; when it occurs, people may experience a strong want to scratch their skin. Raised, itchy, red spots on the skin are known as hives. 

They may combine to produce bigger swollen regions and might vary in size. Hives can form anywhere on the body, and itching is frequently present [3].

Consuming allergic foods can cause eczema symptoms in those who already have them (atopic dermatitis). 

Patches of skin that are itchy, red, and inflamed are frequently the consequence of eczema flare-ups.

Respiratory symptoms

After ingesting the trigger food, some people may develop sneezing fits or a protracted runny nose. Itching or inflammation in the nasal passages may also accompany this.

Foods that trigger allergies can congest the nose, making it challenging to breathe through the nose. 

Food allergy sufferers may get a chronic cough or wheeze, which is a high-pitched whistling sound made during breathing. Narrowing of the airways is frequently linked to wheezing.


Breathing might become challenging due to narrowed airways. Additionally possible is wheezing, a high-pitched whistling sound made during breathing.

It is possible for the throat or tongue to swell suddenly, creating a stiffness that makes it challenging to swallow or talk.

Moreover, the body’s reaction to the allergic reaction may be accompanied by an elevated heart rate or a weak pulse.

What are the common adult-onset food allergies?

Despite the fact that food allergies are frequently linked with children, it’s vital to understand that adults can develop them as they age. 

Even if you’ve eaten the dish in question before without experiencing any problems, adult-onset food allergies might strike quickly. 

The following list of typical adult-onset food allergies:

Gluten allergy

Consuming gluten, a protein in wheat, barley, and rye, causes gluten intolerance, an autoimmune condition. Digestive problems, stomach discomfort, bloating, diarrhea and exhaustion are among the symptoms.

Shellfish allergy

Adults who are allergic to shellfish, such as shrimp, lobster, crab and scallops, may experience allergic responses. 

Hives, itchiness, stomach issues, swelling of the face or throat and breathing difficulties are just a few of the possible symptoms.

Tree nut allergy

Allergies can be brought on by tree nuts such as almonds, walnuts, cashews and pistachios. From minor itching and hives to severe responses like anaphylaxis, symptoms might vary.

Soy allergy

Adults may experience adverse responses to soy and soy products. Skin rashes, itching, swelling, digestive problems and in severe cases, anaphylaxis, may all be symptoms.

Dairy allergy

To dairy products, especially cow’s milk, some individuals develop allergies. Stomach pain, bloating, diarrhea, skin rashes and respiratory issues are just a few symptoms that may appear.

What are the 10 signs you’ve developed a food allergy as an adult?

Being diagnosed with a food allergy as an adult might be unexpected and upsetting to your daily routine. 

While it’s common to link food allergies with children, it’s vital to remember that they can appear at any age. Ten signs that you may have a food allergy as an adult include:

1. Sudden onset of symptoms

A food allergy may be present if you start having allergic responses soon after eating a particular meal. After intake, these effects may start to manifest minutes to hours later.

2. Itchy or tingling sensation in the mouth

A food allergy may be detected by symptoms of itching or tingling in the mouth, lips or throat after eating particular foods.

Oral allergy syndrome, often known as this symptom, is frequently linked to pollen cross-reactivity with particular fruits, vegetables or nuts.

3. Swelling of the lips, tongue or face

In especially around the face, lips or eyes, allergic responses might result in observable swelling. 

Angioedema, a more noticeable kind of swelling, can range from moderate to severe. Lips, tongue or throat swelling may potentially be a sign of a more serious allergic response.

4. Skin reactions

An allergic response may be indicated by the development of hives (raised, red, itchy lumps on the skin), redness or itchy skin after consuming a particular meal. 

Any area of the body might experience these skin responses, and they sometimes come with a warm feeling.

5. Gastrointestinal symptoms

A food allergy may be indicated by persistent cramps, diarrhea, vomiting, or stomach discomfort after eating. 

It’s important to examine the potential of a food allergy as the reason since these symptoms might match those of food poisoning or other digestive problems.

6. Respiratory issues

After consuming particular foods, wheezing (a high-pitched whistling sound made during breathing), shortness of breath, coughing or a tightness in the chest may indicate a food allergy.

These respiratory symptoms may include nasal congestion or itching and can range in severity from moderate to severe.

7. Nasal congestion or runny nose

Consuming allergenic foods might cause allergic rhinitis symptoms such nasal congestion, sneezing or a runny nose. 

People who have cross-reactivity with specific meals and pollen allergies frequently experience this.

8. Nausea or vomiting

A food allergy may be present if you frequently feel queasy or vomit after consuming a certain meal. 

The immune system’s reaction to the allergenic food may be responsible for these gastrointestinal symptoms [4].

9. Fatigue or lethargy

After ingesting some foods, feeling too exhausted or lacking in energy might be a sign of a food allergy. The immune system’s reaction to the allergenic food, which might cause inflammation and weariness, can be held responsible for this.

10. Anaphylaxis

The most severe allergic reaction, anaphylaxis, can happen rapidly and includes a number of symptoms. 

Breathing issues, swelling (particularly in the face or throat), lightheadedness, an accelerated heartbeat and a reduction in blood pressure are a few of these that may occur. 

Anaphylaxis is a medical emergency that has to be treated right away.


Finding out you have a food allergy as an adult might be difficult. Recognizing the symptoms and signs is essential for prompt diagnosis and effective treatment. 

It’s crucial to speak with a doctor or allergist if you suddenly get symptoms like itchiness, swelling, gastrointestinal difficulties or respiratory problems after ingesting a particular food. 

You can manage your food choices, avoid allergens, and reduce the risk of life-threatening allergic responses with the right examination, diagnosis and advice. 

You may successfully manage your adult-onset food allergy and have a secure and healthy life by being knowledgeable and proactive.


Can adults develop food allergies out of nowhere?

Yes, the immune system can become sensitive to particular proteins, resulting in the emergence of an allergic reaction, even though the person has taken the meal in the past without experiencing any problems.

How long does it take to get a diagnosis for a food allergy?

The length of time it takes to be diagnosed with a food allergy might vary based on a number of variables, including the accessibility of medical services and the particular diagnostic procedures needed. The procedure can often take a few weeks to several months since it frequently entails a careful assessment of the patient’s medical history, allergy testing, and occasionally elimination diets or oral food challenges to identify the allergen.

Can food allergies be outgrown?

Yes, although the possibility of a food allergy outgrowing varies based on the allergen. Allergies to peanuts, tree nuts, fish, and shellfish typically last into adulthood, but those to milk, eggs, soy, and wheat are more probable to overcome.

[1] https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/food-allergy-and-intolerance
[2] https://www.mayoclinic.org/diseases-conditions/food-allergy/symptoms-causes/syc-20355095
[3] https://www.webmd.com/allergies/skin-allergy-types-triggers
[4] https://www.everydayhealth.com/digestive-health/experts-how-do-food-allergies-affect-digestion.aspx

Photograph: jirkaejc/Envato
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