Food Intolerance Causes and Triggers: A Guide for UAE Residents

Food intolerance can be difficult to identify because digestive symptoms may appear hours after eating and can have several possible causes. Bloating, gas, abdominal pain, diarrhoea, nausea and changes in bowel habits may sometimes be associated with food intolerance, but similar symptoms can also occur with other digestive conditions.

Understanding what causes food intolerance, which foods or ingredients may trigger symptoms, and how potential triggers can be identified can help you make more informed decisions about your diet and when to seek medical advice.

This guide explains the common causes and triggers of food intolerance and what UAE residents should know when dealing with recurring food-related symptoms.

What Is Food Intolerance?

Food intolerance occurs when the body has difficulty digesting or processing a particular food or an ingredient in food. It is different from a food allergy, which involves the immune system and can cause a serious allergic reaction.

Symptoms of food intolerance commonly involve the digestive system and may appear several hours after consuming the food or ingredient.

Not every digestive symptom means that you have a food intolerance. Conditions such as irritable bowel syndrome, coeliac disease and other gastrointestinal disorders can produce similar symptoms, which is why persistent symptoms should be medically assessed.

What Causes Food Intolerance?

There is no single cause of food intolerance. Different types of intolerance can develop for different reasons.

Some common mechanisms include:

1. Difficulty Digesting Specific Food Components

One of the best-known examples is lactose intolerance.

Lactose is the natural sugar found in milk and many dairy products. People with lactose intolerance have difficulty digesting lactose because their small intestine produces insufficient lactase, the enzyme needed to break it down. Undigested lactose can then reach the colon, where bacteria break it down and produce gas and fluid that may lead to symptoms.

2. Enzyme Deficiencies

Certain food intolerances occur when the body does not produce enough of a particular enzyme needed to digest a food component.

Lactase deficiency is a common example. Lactase levels can naturally decrease with age in some people, while damage to the small intestine from certain diseases or conditions can also contribute to lactose intolerance.

3. Sensitivity to Certain Food Components

Some people may experience symptoms after consuming particular ingredients or food components.

Depending on the individual, possible triggers can include:

• Lactose

• Certain carbohydrates

• Caffeine

• Alcohol

• Sulphites

• Certain food additives

• Other ingredients that an individual may have difficulty processing

The specific trigger and level of tolerance can vary considerably between individuals.

4. Underlying Digestive Conditions

Some food-related symptoms may occur because an underlying digestive condition is affecting how the body processes certain foods.

For example, damage to the small intestine caused by conditions such as coeliac disease or Crohn's disease can contribute to secondary lactose intolerance. In some cases, treating the underlying condition may improve lactose tolerance.

This is one reason it is important not to assume that every recurring digestive symptom is simply a food intolerance.

What Are Common Food Intolerance Triggers?

The foods that trigger symptoms depend on the individual.

Lactose and Dairy Products

Lactose is one of the most commonly recognised food intolerance triggers. It is naturally found in milk and dairy products.

Symptoms may include:

• Bloating

• Gas

• Abdominal pain

• Diarrhoea

• Nausea

Symptoms can vary depending on the amount of lactose consumed. Many people with lactose intolerance can tolerate some amount of lactose without significant symptoms.

Certain Carbohydrates

Some people experience digestive symptoms after consuming particular carbohydrates that are difficult for them to digest or absorb.

The response can vary depending on the individual, the amount consumed and other dietary factors.

Food Additives and Ingredients

Some people report symptoms after consuming certain additives or ingredients. Examples described in food intolerance guidance include sulphites, caffeine and some preservatives.

However, an ingredient should not automatically be considered the cause of symptoms simply because symptoms occur after eating it. A healthcare professional can help determine whether further evaluation is appropriate.

Why Do Food Intolerance Symptoms Differ From Person to Person?

Food intolerance is not necessarily an all-or-nothing condition.

The amount of a food consumed can affect whether symptoms appear and how severe they become. For example, people with lactose intolerance may tolerate smaller amounts of lactose but experience symptoms after consuming larger quantities.

Other factors, including the type of food, portion size and an individual's digestive health, may also influence symptoms.

This is why a universal list of foods that everyone with food intolerance must avoid is not appropriate.

What Are the Common Symptoms of Food Intolerance?

Symptoms can vary depending on the food, the underlying mechanism and the amount consumed.

Common symptoms may include:

• Bloating

• Gas

• Abdominal pain

• Diarrhoea

• Nausea

• Constipation

• Indigestion

• Stomach discomfort

Symptoms may occur several hours after eating and can sometimes last for hours or days.

If symptoms repeatedly occur after eating, keeping a food and symptom diary can help you identify patterns that can then be discussed with a healthcare professional.

For more information about when recurring symptoms may require further assessment, read our guide on signs you might need a food intolerance test.

How Can You Identify Your Food Triggers?

Identifying a possible food trigger usually involves looking at the relationship between your diet, symptoms and medical history.

Keep a Food and Symptom Diary

Record:

• What you ate and drank

• The approximate portion

• When you ate it

• When symptoms appeared

• Which symptoms occurred

• How severe the symptoms were

• How long the symptoms lasted

A detailed dietary history and written food records can provide useful information when a healthcare professional is assessing whether food may be contributing to symptoms.

Consider Guided Elimination and Reintroduction

In some cases, a healthcare professional may recommend temporarily avoiding a suspected food and then reintroducing it while monitoring symptoms.

The NHS describes elimination and reintroduction as one approach that may be used when investigating suspected food intolerance.

However, elimination diets should be approached carefully. Removing multiple foods without professional guidance can make it difficult to maintain adequate nutrition.

Discuss Symptoms With a Healthcare Professional

A healthcare professional may review your symptoms, eating habits, family history and medical history. Depending on the suspected condition, additional testing may be appropriate.

For example, lactose intolerance may be evaluated using medical history, dietary changes and, when appropriate, a hydrogen breath test.

If you are considering testing, you can read our guide on how to prepare for a food intolerance test.

Is Food Intolerance the Same as Food Allergy?

No. Food intolerance and food allergy are different conditions.

Food intolerance generally relates to difficulty digesting or processing a food or ingredient. Food allergy involves an immune response and can cause potentially serious reactions.

Food allergy symptoms can include:

• Hives

• Swelling

• Vomiting

• Wheezing

• Difficulty breathing

• Anaphylaxis

If you experience difficulty breathing, swelling of the throat or tongue, fainting or other signs of a severe allergic reaction after eating, seek emergency medical care.

For a detailed comparison, read our guide on food intolerance vs food allergy: symptoms and testing.

Are Food Intolerance Tests Always Necessary?

Not every person with digestive symptoms needs food intolerance testing.

The appropriate evaluation depends on your symptoms, medical history and the suspected condition. For example, lactose intolerance can sometimes be assessed through symptoms, dietary changes and specific clinical testing when appropriate.

It is also important to be cautious about commercially available tests that claim to identify a large number of food sensitivities.

The American Academy of Allergy, Asthma & Immunology states that IgG food panel testing has not been scientifically proven to diagnose food sensitivities or intolerances and recommends against using it for this purpose.

Therefore, testing decisions should be discussed with a qualified healthcare professional rather than relying solely on commercial home-test claims.

When Should You See a Doctor?

Speak with a healthcare professional if digestive symptoms:

• Keep coming back

• Are severe or worsening

• Interfere with your daily activities

• Are associated with unexplained weight loss

• Require you to eliminate several foods

• Continue despite dietary changes

• Cause concern about nutritional deficiencies

Persistent digestive symptoms can have causes other than food intolerance, so proper assessment is important.

Food Intolerance in the UAE: What Should Residents Know?

Dubai and the wider UAE offer a diverse food environment, with Middle Eastern, South Asian, European and international cuisines widely available.

If you suspect a food intolerance, practical steps can include:

• Checking food labels carefully.

• Keeping a food and symptom diary.

• Asking restaurants about ingredients.

• Paying attention to portion sizes.

• Avoiding unnecessary elimination of multiple foods.

• Discussing persistent symptoms with a healthcare professional.

When eating out, remember that food intolerance and food allergy are different. People with diagnosed food allergies need particularly careful precautions because allergic reactions can be serious.

Conclusion

Food intolerance can have different causes, and the foods that trigger symptoms can vary from one person to another. Understanding the possible causes, tracking symptoms and seeking appropriate medical guidance can help you make informed decisions about your diet.

Avoid unnecessary food restrictions and be cautious about tests that make broad claims without strong scientific evidence.

If recurring digestive symptoms are affecting your daily life, speak with a qualified healthcare professional to determine the most appropriate way to investigate and manage them.

Dr. Mahmoud Musa

General Practitioner

Dr. Mahmoud Musa is a dedicated General Practitioner committed to evidence-based healthcare. He reviews medical and wellness content with a focus on scientific accuracy, clarity, and practical value, helping readers understand health information through simple, reliable, and informative guidance.