Food Allergies and Intolerance in African Adults: Causes, Diagnosis and Prevention

By Victory Onyenekwe. B.Sc. Ed Physical and Health Education. Freelance Health Writer. Medically reviewed by The DLHA Team.

March 28, 2026

An African female patient receives oxygen by nasal mask for a severe allergic reaction, in a busy hospital emergency centre. Image credit: Google Gemini. Click on image to enlarge.

 

Highlights

• Immune vs. Digestive Systems: A food allergy is an immune system reaction to food proteins that can be life-threatening, whereas food intolerance is a digestive system issue, often caused by enzyme deficiencies, that results in "digestive inconvenience" like bloating or gas.

• Regional African Allergens: While Africans react to global allergens like milk and eggs, the local landscape includes specific regional triggers such as pineapple, okra, cassava, and mopane worms.  

• Perception vs. Clinical Reality: There is a notable gap between perceived and actual allergy rates; while self-reported rates reach up to 19% in some regions, clinical testing in parts of Ghana and Nigeria shows a true prevalence of only 3–5%.  

• Common Diagnostic Pitfalls: Over-reliance on blood (IgE) tests is a frequent mistake, as these tests can produce false positives in up to 50% of cases and often indicate sensitization rather than a true, functional allergy.

• Gender and Age Dynamics: Food allergy prevalence shifts over time; while boys are more commonly affected during childhood, women become more likely to develop allergies as they get older due to hormonal influences.  

 

Introduction

“Africans never have food allergies.” How many times have you heard this?

For most African adults, food allergies are often viewed as a foreign concept peculiar to our Western counterparts. Ingrained in our minds is the assumption that we cannot be allergic to our traditional meals. This belief is reinforced by a lack of data, as localized studies on food allergies are minimal, with many reported claims of “allergy” in African adults actually turn out to be food intolerances. 

Distinguishing between the two is vital: one is a digestive inconvenience, while the other can be life-threatening leading to severe breathing and cardiovascular problems (anaphylaxis). Consequently, food allergies are not something that should be ignored. 

In this article we examine the critical differences between food allergies and intolerance, how they are diagnosed and actionable prevention and management tailored to the African context.

 

What is Food Allergy?

A food allergy is a reaction to a food protein that occurs in the immune system. The body mistakenly considers this food protein as harmful, triggering a protective response. Food allergy responses can be categorized into the following:

IgE-Mediated Food Allergies: The IgE (Immunoglobulin E) is an antibody in the immune system that is triggered when the body is exposed to an allergen. An example of this category of allergy is the Pollen-Food Allergy Syndrome, a condition where an individual’s body is already sensitized to certain pollens such as grass. The body then confuses the proteins in raw vegetables and fruits for the pollen proteins it is allergic to. This syndrome often appears when eating raw fruit or salads; however, the cross-reactive proteins can be destroyed when cooked. 

Symptoms of an IgE-mediated food allergy occur within seconds or minutes of consumption or exposure to an allergen.

Non- IgE Mediated Food Allergies: This allergic reaction occurs without involving the IgE antibody. Symptoms are delayed, typically developing between 2 to 72 hours. This makes them harder to identify through medical screening. Standard food allergy tests such as the skin-prick test and blood test usually return negative results in these cases because they only screen for IgE antibodies.

Mixed IgE and Non-IgE-mediated: This is a combination of both IgE and non-IgE reactions

 

What is Food Intolerance?

Food intolerance is the inability of an individuals’ body to digest certain food substances found in particular meals. Generally resulting in bloating, flatulence (farting) or diarrhoea. This is usually caused by an enzyme deficiency, sensitivity to food additives, or a reaction to naturally occurring chemicals. Food intolerance takes place in the digestive system.

 

How does Food Allergy Differ from Food Intolerance?

• System Affected: A food allergy affects the immune system, while food intolerance primarily affects the digestive system.

• Response Time: Allergic reactions are typically immediate whereas intolerance can take several hours or days to occur.

• Tolerance Levels: Allergens cannot be consumed even in tiny amounts without a reaction, while small amounts of a food causing intolerance may sometimes be tolerated by the body.

 

How Common is Food Allergy in Africa?

Infographics showing burden of food allergies in Africa relative to all allergic reactions. Click on image to enlarge.

 

While localised research is limited, available studies suggest that food allergies account for anywhere from 5% to nearly 50% of all allergic reactions across the continent. [1]

Emerging evidence indicates that food allergy is becoming a significant health concern in Africa, mirroring trends previously seen in Western nations. In South Africa, 42% of children with atopic dermatitis were confirmed to have a food allergy through oral food challenges, with peanut allergy rates within this group reaching 26%.

The data also highlights a gap between perception and clinical reality. While self-reported allergy rates in some regions are as high as 17-19%, clinical testing in parts of Ghana and Nigeria reveals a lower true prevalence of 3-5%. Furthermore, the African allergenic landscapes are distinguished from Western patterns by regional allergens like pineapple, okra and mopane worm.[2]

Ultimately, a lack of clinical resources and limited access to testing facilities in many countries continue to hinder the collection of comprehensive data.

 

Common Food Reactions Globally

While Africans can be allergic to common global allergens, there are regional allergens that differentiate the African allergenic landscape from its Western counterparts, largely due to variations in local diets and regional environments.

The top 9 global allergens are:

• Milk
• Egg
• Peanut
• Tree nuts (cashews, almonds, walnuts etc.)
• Shellfish
• Fish
• Soy 
• Sesame 
• Wheat 

 

Common Foods That Africans are Allergic To

Info poster showing the common food allergens in African adults. Image credit: Google Gemini. Click on image to enlarge.

 

Here is a list of the common foods in Africa that people are usually allergic to:

• Peanuts
• Eggs
• Fish 
• Shellfish (crayfish and prawns)
• Cow’s milk
• Pineapple 
• Okra 
• Mopane worm
• Cassava

Related: Allergies on the Rise in Africa 

 

What are Common Foods That Africans are Intolerant of?

Food intolerance across the African continent is most commonly linked to lactose (dairy). But the use of traditional fermented products often breaks down lactose and makes it easier to digest.

Other intolerances can arise from fructose in high-sugar fruits and honey, as well as gluten. Often, these intolerances go unrecorded because many individuals primarily consume indigenous staples, meaning they may not be frequently exposed to high fructose and gluten-containing foods enough to realize they have a sensitivity to them.

 

What are the Symptoms of Food Allergy versus Intolerance?

Info poster displaying the symptoms of food allergies and intolerance. Image credit: Google Gemini. Click on image to enlarge.

 

Symptoms of Food Allergies

Food allergy symptoms typically occur within minutes and may involve the skin, gastrointestinal tract, respiratory system, and cardiovascular system. The following are common symptoms of food allergies:

• Itching in the mouth
• Skin rash or hives
• Swelling of the lips, throat, face or tongue
• Abdominal pain
• Vomiting
• Dizziness
• Sneezing 
• Runny nose
• Diarrhoea 
• Anaphylaxis (This is a severe reaction to an allergen that leads to tightening of the airways, rapid pulse and loss of consciousness).

Symptoms of Food Intolerance

Some common symptoms of food intolerance include:

• Bloating
• Diarrhoea
• Flatulence (farting)
• Nausea
• Vomiting
• Stomach cramps
• Headaches 
• Fatigue
• Rashes
• Runny nose

 

How are Food Allergies and Food Intolerance Diagnosed?

Info poster showing steps in the diagnosis of food allergies. Image credit: Google Gemini. Click on image to enlarge.

 

Diagnosis of food allergy in Africa, remains challenging. In many settings, adequate facilities for food allergy testing are lacking. Additionally, allergic reactions are often overlooked especially when they are not life-threatening. 

Here are the steps involved in the diagnosis of food allergies

I. Clinical History and Physical Exam: A doctor will conduct a comprehensive medical review, which includes evaluating:

• Symptom Profile: Identifying the specific nature of the allergy reactions
• Reaction Timing: Determining how quickly the symptoms appear after consuming or coming in contact with a potential allergen
• Dietary Specifics: Identifying the exact food and the amount consumed
• Reaction History: Assessing a record of previous reactions and their level of severity
• Genetic factors: Evaluating family history for allergies, eczema and asthma
• Physical Examination: A clinical assessment for signs of eczema, chronic rashes or other visible allergic reactions.

II. Allergy Testing: An allergy test can be carried out in two ways:

• Skin Prick Test: In a skin prick test, the patient is exposed to specific potential allergens to determine the level of sensitization. To perform the test, small drops of an allergen solution are placed on the skin, which is then lightly pricked with a needle. The appearance of a raised itchy bump known as a wheal suggests a sensitisation to that food. 

It is important to note that a positive skin prick test does not always indicate a true allergy. If a patient is scheduled for this test, and is currently taking antihistamines, the medication should be stopped two- five days before the test will be carried out, to ensure accurate results.

• Blood Test [Specific IgE test]: This test screens the patient’s blood for the presence of the immunoglobulin E in the body, to specific foods, pollens or medications. It is done to determine sensitisation to specific allergen, particularly useful when a skin test cannot be conducted due to severe eczema or a high risk of a severe reaction. 

Unlike skin test, the blood test is not affected by antihistamines. However, they show sensitisation rather than certainty as blood tests can yield false positive results. 

III. Elimination Diet: This involves removing specific foods suspected of triggering an allergic reaction. Symptoms are closely monitored, followed by a supervised reintroduction of the suspected food to the patient. This process should only be done under medical guidance.

IV. Oral Food Challenge (OFC): Considered the most accurate form of diagnosis of food allergy. OFC involves giving a patient an increasing amounts of a suspected allergen to confirm or rule out an allergy. This must only be conducted under strict medical supervision. 

Related: Eczema in African Adults: Causes, Types and Symptoms

 

What are the Most Common Mistakes in Food Allergy Testing?

Food allergy testing is not without its faults or flaws. Here are some common mistakes in food allergy testing:

• Over-Reliance on Blood Tests Alone: A frequent error is using Serum IgE tests as the primary diagnostic tool, despite their tendency to produce ‘false positives’ in up to 50% of cases. [3]

• Testing Without a Specific History: Ordering allergy tests for patients who show no physical symptoms after consuming a suspected allergen. In these groups, the accuracy of the test can be as low as 2.2%.[3]

• Confusing Sensitisation with Allergy: Many people mistakenly believe a positive lab result equals a life-threatening allergy. But in reality, a positive test often means the immune systems recognise the allergen (sensitisation), but the person can still eat it safely. [3]

• Relying Solely on Broad Commercial Panels: Testing for a wide range of foods, including unlikely triggers like corn, is a common pitfall that leads to identifying irrelevant sensitivities.

• Mislabelling Food Intolerance as Allergies: Non-immune reactions labelled as an allergy is actually the body’s intolerance to the food. For example, lactose intolerance which is a digestive issue is often misdiagnosed as a dairy allergy which is an immune reaction.

• Assuming Test Levels Predict Severity: A lot of individuals have a major misconception that a higher IgE level in the blood means a person will have more anaphylactic reaction.

• Unnecessary Dietary Restrictions: Removing healthy foods from a diet based solely on a lab test is a clinical mistake that can lead to nutritional deficiencies.

• Failure to Confirm with a Food Challenge: The Oral Food Challenge (OFC) remains the gold standard for diagnosing food allergies, as it is the most definitive way to confirm a reaction. Despite its accuracy, many diagnoses are still made without performing this essential test.

 

How can Food Allergies be Managed?

Effective management of food allergies in African adults should focus on preventing exposure, identifying reactions promptly, treating symptoms, and public awareness.

• Allergen Avoidance: Total awareness and avoidance of identified food allergens is key. This requires reading food labels and avoiding cross-contamination.

• Emergency Preparedness: Individuals must always have an emergency action plan. Family, friends and colleagues should be trained to be on the lookout for symptoms and understand that emergency medications, such as epinephrine must be available for severe reactions like anaphylaxis.

• Nutritional Management: Allergic foods should be substituted with healthy alternatives to ensure a balanced diet and prevent malnutrition. It is important to monitor overall health and wellness when making these dietary changes.

• Medical Follow-up: Adults should attend regular medical check-ups for periodic reassessment, as some food allergies can change over time. This medical follow-up assists in managing related allergic conditions like asthma and eczema.

Related: Asthma in African Children: Causes, Symptoms and Care  

 

Prevention of Food Allergies in African Adults

• Introduction of Allergenic Foods: For adults who have previously avoided certain foods without a confirmed diagnosis, introducing potential allergens under the guidance of healthcare professionals may help reduce the risk.

• Diversified Meals: Consuming a wide range of diverse meals, focusing on nutrient-dense, traditional meals, supports the maintenance of immune tolerance within the body.

• Proactive Medical Reassessment: Adults should engage in periodic medical check-up to reassess their allergies, as some conditions can change over time or be better managed alongside other allergic conditions like eczema or asthma.

• Education and Awareness: It is critical for adults, their families, and colleagues to be educated on recognizing the signs of an allergic reaction. This includes knowing how to administer emergency medications such as epinephrine, in the event of a severe reaction like anaphylaxis.

• Public Health Awareness: Creating community awareness campaigns regarding food allergies in low-resource settings. This includes establishing allergy care within primary healthcare systems, improving access to diagnostic facilities and implementing clear food labelling regulations for all consumable products.

 

Conclusion

It is critical to recognize that Africans are not immune to food allergies. There is a profound need for increased investment in well-designed, appropriate studies to generate accurate data and reliable evidence specifically for this demographic.

This evidence will support the development of effective health policies and targeted interventions, ensuring that Africans have access to proper diagnosis, specialized treatment, and long-term care for food allergies.

Additionally, raising public awareness and strengthening local healthcare infrastructure are essential steps toward reducing misconceptions and improving clinical outcomes for affected adults. By prioritizing education for both the public and healthcare providers, we can reduce the risk of misdiagnosis and ensure that people do not cut out important traditional foods without a medical reason.

 

Frequently Asked Question (FAQ)

• Do Men and Women Develop Food Allergies Equally?

No, Men and women do not develop food allergies equally. At childhood and adolescence boys are more likely to be affected by food allergies than girls. However, as women get older, they become more likely to be affected by food allergies due to hormonal influences with oestrogen producing a stronger immune response. This higher prevalence normalizes or decreases as menopause sets in.

• Can I Develop an Allergy to Food I have eaten for Years?

Yes, you can develop an allergy to food consumed for years. This new reaction can be triggered by environmental changes, or a prolonged break from eating a specific food.

• Is Food Intolerance the Same as Food Poisoning?

No, food intolerance is not the same as food poisoning. Food intolerance is your body’s inability to digest certain substances found in your food, leading to bloating, flatulence and diarrhoea while food poisoning is an acute illness that is caused by the consumption of food that has been contaminated by bacteria, viruses or toxins generally resulting in fever and vomiting.

 

References: 

1. Mvoundza Ndjindji O, Djoba Siawaya JF. Mapping Allergic Diseases in Sub-Saharan Africa. Front Allergy. 2022; 3:850291. Doi:10.3389/falgy.2022.850291. Available from here.

2. Kung SJ, Steenhoff AP, Gray C. Food allergy in Africa: myth or reality? Clin Rev Allergy Immunol. 2014 Jun;46(3):241-9. doi: 10.1007/s12016-012-8341-z. (Abstract). Available from here.

3. Fleischer D, Burks A. Pitfalls in Food Allergy Testing Diagnosis: Serum IgE Testing. The Journal of Pediatrics. 2014;166.8-10. (Editorial). Available from here.

 

 

Published: March 28, 2026

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