In what ways are food allergies and food intolerance difference

A food allergy is an exaggerated immune system response to a food protein and the body triggers an allergic reaction. Symptoms can include hives, itching, swelling, vomiting, diarrhoea and nausea. In some cases, it can cause potentially life-threatening symptoms, called anaphylaxis, either by breathing difficulties and/or a sudden drop in blood pressure.

Sometimes food allergy may be less obvious and can be characterised by infantile colic, reflux of stomach contents, eczema, chronic diarrhoea, and failure to thrive. Recent studies own found that up to 40-50 per cent of eczema cases in young children are triggered by food allergy.

Eight foods cause 90 per cent of allergies: milk, egg, peanuts, tree nuts, fish, shell fish, wheat and soy.

However, any food can cause an allergic reaction.

A food intolerance is an adverse reaction to a food that does not involve the immune system. Reactions can be immediate or delayed up to 20 hours after a food is eaten.

Symptoms of intolerance are sometimes vague and can include a combination of the following: gastrointestinal problems such as bloating and wind, diarrhoea, nausea and indigestion, aggravation of eczema or asthma. Food intolerances can sometimes mimic symptoms of other medical conditions — it is significant to get checked out by a doctor to eliminate other problems first.

Further information:

Food allergy Food intolerance

Physical reactions to certain foods are common, but most are caused by a food intolerance rather than a food allergy.

A food intolerance can cause some of the same signs and symptoms as a food allergy, so people often confuse the two.

A true food allergy causes an immune system reaction that affects numerous organs in the body. It can cause a range of symptoms. In some cases, an allergic food reaction can be severe or life-threatening. In contrast, food intolerance symptoms are generally less serious and often limited to digestive problems.

If you own a food intolerance, you may be capable to eat little amounts of the offending food without trouble. You may also be capable to prevent a reaction. For example, if you own lactose intolerance, you may be capable to drink lactose-free milk or take lactase enzyme pills (Lactaid) to aid digestion.

What are the symptoms of food intolerance?

Symptoms of food intolerance tend to take longer to appear than symptoms of allergies

  1. Headaches/Migraines
  2. Diarrhea
  3. Gas, cramps or bloating
  4. Vomiting
  5. Stomach pain
  6. Heartburn
  7. Irritability or nervousness
  8. Cough
  9. Nausea
  10. Feeling under the weather
  11. Runny nose
  12. Bloating
  13. Irritable bowel

What are the symptoms of a food allergy?

Symptoms of a food allergy can range from mild to severe, and the quantity of food necessary to trigger a reaction varies from person to person, this can include:

  1. Diarrhea
  2. Cramping stomach pain
  3. Nausea
  4. Rash or hives
  5. Itchy skin
  6. Shortness of breath
  7. Chest pain
  8. Swelling of the airways to the lungs

Anaphylaxis is a extremely serious and potentially fatal allergic reaction that involves a sudden drop in blood pressure, loss of consciousness and body system failure.

Causes of food intolerance include:

Absence of an enzyme needed to fully digest a food – Lactose intolerance is a common example.

Irritable bowel syndrome – This chronic condition can cause cramping, constipation and diarrhea.

Sensitivity to food additives – E.g.

sulfites used to preserve dried fruit, canned goods and wine can trigger asthma attacks in sensitive people.

Recurring stress or psychological factors – Sometimes the mere thought of a food may make you ill. The reason is not fully understood.

Celiac disease Celiac disease has some features of a true food allergy because it involves the immune system.

In what ways are food allergies and food intolerance difference

However, symptoms are mostly gastrointestinal, and people with celiac disease are not at risk of anaphylaxis. This chronic digestive condition is triggered by eating gluten, a protein found in wheat and other grains.

How common are food allergies and intolerances?

Food allergies affect about 1 percent of adults and 7 percent of children, although some children outgrow their allergies. Food intolerances are much more common. In fact, almost everyone at one time has had an unpleasant reaction to something they ate.

Some people own specific food intolerances. Lactose intolerance, the most common specific food intolerance, affects about 10 percent of Americans.


It is not simple to determine whether somebody has a food intolerance or allergy because the signs and symptoms often overlap. Certain patterns in the symptoms can assist a doctor distinguish between the two. In the vast majority of cases, food intolerance symptoms take much longer to appear than food allergies.

Patients are advised to hold a diary and record below which foods are eaten, what the symptoms were love, and when they appeared.

The data in the diary can assist a dietician or doctor identify which foods are causing adverse reactions, and what steps to take.

Skin prick tests are not 100 percent reliable.

Apart from lactose intolerance and celiac disease, there is no precise, dependable, and validated test to identify food intolerance. The best diagnostic tool is an exclusion diet, also known as an elimination or diagnostic diet.

Intolerance to regularly-eaten foods may result in adverse reactions running into each other.

When this occurs, it is hard to identify which foods are to blame. There is a higher risk that a chronic condition or disease is erroneously diagnosed.

Exclusion diets are extremely useful in isolating the culprit foods.

In a typical exclusion diet, the suspected food is removed from the diet for a set period, generally between 2 weeks and 2 months. If during this period the adverse reactions resolve, it becomes more likely that the culprit has been found. This can be further confirmed if it is then reintroduced and symptoms return.


The doctor may recommend a skin test and/or a blood test to law out a food allergy:

Skin prick test – this determines the patient’s reaction to a specific food.

A little quantity of the suspected food is placed on the patient’s back or forearm.

In what ways are food allergies and food intolerance difference

The skin is pricked with a needle, allowing some of its substance to penetrate under the skin surface. Allergic people will react with a raised bump.

In what ways are food allergies and food intolerance difference

However, skin prick tests are not 100 percent reliable.

Blood test – this measures levels of IgE (immunoglobulin E) antibodies. These tests are not 100 percent dependable either. The presence of IgE antibodies may be a part of the normal human response and indicate tolerance, rather than an adverse reaction, according to a study published in CMAJ.


The best current treatment for food intolerance is to either avoid certain foods or eat them less often and in smaller amounts, as well as taking supplements that may assist digestion.

Some people discover that if they stay off the specific food for a while, they own no reaction when eating it again – this is known as tolerance.

Maintaining tolerance is often a question of knowing how endless to abstain and how much of it to eat when it is being reintroduced.

As each person reacts differently, the only way to determine this is by trial-and-error.

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en español¿En qué se diferencia una alergia alimentaria de una intolerancia alimentaria?

What is the difference between food allergies and food intolerances?

Food allergies and food intolerances (or sensitivities) can own similar symptoms, but are extremely diverse conditions:

A food intolerance means either the body cannot properly digest the food that is eaten, or that a specific food might irritate the digestive system.

Symptoms of food intolerance can include nausea, gas, cramps, abdominal pain, diarrhea, irritability, nervousness, or headaches.

A food allergy happens when the body’s immune system, which normally fights infections, sees the food as an invader. This leads to an allergic reaction — a response from the immune system in which chemicals love histamine are released in the body. The reaction can cause symptoms love breathing problems, throat tightness, hoarseness, coughing, vomiting, abdominal pain, hives, swelling, or a drop in blood pressure.

Even if previous reactions own been mild, someone with a food allergy is always at risk of the next reaction being life-threatening.

Eating a microscopic quantity of the food, or sometimes even touching or inhaling it, could lead to anaphylaxis. So anyone with a food allergy must avoid the problem food(s) entirely and always carry emergency injectable epinephrine.

Many people with food sensitivities, on the other hand, can ingest a little quantity of the bothersome food without a problem.

People are quick to eliminate certain foods from their diets, chalking every adverse reaction up to an allergy, but there’s a large difference between food allergies and food intolerances.

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“Food allergies are genuine and they can be deadly,” says holistic nutritionist Tara Miller.

“Food allergies will release IgE antibodies, which own an immediate effect and can lead to things love an anaphylactic shock. Whereas intolerances release IgG, which is more of an inflammation response.”

What’s a food intolerance?

A food intolerance, on the other hand, is a digestive system response that results from consuming something that the body can’t break below or digest.

It manifests itself in gut reactions that include stomach pain, bloating, gas, diarrhea, heartburn and vomiting.

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There are a variety of reasons a person may own an intolerance, including lacking an enzyme needed to digest the food, a sensitivity to additives or chemicals (like sulfites, for example, which are used to preserve canned goods and wine), or IBS. Unlike a food allergy, however, people with a food intolerance can typically eat a little quantity of the offending food without having any reactions.

What’s a food allergy?

There are eight foods that account for 90 per cent of allergic reactions — peanuts, tree nuts, shellfish, fish, eggs, milk, wheat and soybeans — and their effects could cause rash or hives, nausea, cramps, diarrhea, chest pain and shortness of breath.

In what ways are food allergies and food intolerance difference

In extreme cases, a person can go into anaphylactic shock, a serious and potentially fatal condition that causes a sudden drop in blood pressure, loss of consciousness and body system failure.

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That’s because a food allergy is an immune system response that happens when the body identifies a chemical compound (usually a protein) in a specific food as hazardous, and responds by creating antibodies to fight it. These antibodies include histamine, and where they’re released dictates where (and how) the allergy will appear, whether that’s in the nose and throat, skin, digestive system or chest.

When can you develop an allergy or intolerance?

Although a lot of children can grow out of their food allergies or intolerances — it is estimated that 60 to 80 per cent of young children with a milk or egg allergy will be cleared of it by age 16 — adults may discover that they develop them later in life.

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It’s not unusual, for example, for adults to develop an intolerance to lactose because we stop producing the enzyme required to digest it between the ages of three and five.

In fact, less than 40 per cent of the world’s population can digest lactose after childhood.

“It’s significant to hear to your body. If you’re experiencing bloating or cramping, or even irritability and lack of focus after your meals, you may desire to frolic around with the foods you’re consuming,” Miller says. “But that doesn’t mean you’ll discover the same answers for everyone.”

Are there dangers in cutting out foods unnecessarily?

The most effective way of determining if you own a food intolerance is by following an elimination diet, tracking everything you eat and then experimenting by reintroducing foods slowly so as to narrow below the offending item.

In what ways are food allergies and food intolerance difference

But when it comes to fad diets, love going gluten-free, that’s not the typical tactic, and it can own consequences.

READ MORE: 100 ways to own a happier, healthier and better 2018

“We’ve associated going gluten-free with being healthier and especially with leading to weight loss, and that’s because for someone who is truly gluten intolerant, they’ll feel and glance amazing after they cut it out,” Miller says.

“But you can’t always equate the same thing to yourself. We can’t take one portion of a food group and apply it as a blanket health benefit.”

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In fact, that helpful of attitude can easily backfire on you. While cutting out gluten won’t lead to a nutrient deficiency, it can wreak havoc on your relationship with food and lead to disordered eating.

“Striving for a more restrictive diet has negative consequences on so numerous levels,” she says.

“You could develop anxiety about eating out for fear that a restaurant or a friend’s dinner party won’t be capable to cater to your needs, and some people can tug back socially because of that.”

It can also create a “slippery slope” into dangerous patterns, love extreme restrictions or binge eating, especially if it’s something you love but that you’re denying yourself.

“If you feel better not eating a certain food, it’s OK to avoid it,” Miller says.

“Problems arise when people glance to other people’s diets and apply them to themselves without questioning how they are actually feeling.”

© 2018 Global News, a division of Corus Entertainment Inc.

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Wheat allergy

Wheat allergy, not to be confused with gluten intolerance, is due to proteins contained in wheat and is more common in children than in adults.

In what ways are food allergies and food intolerance difference

The symptoms of this allergy revealed in adults generally appear immediately after ingesting wheat, but can also happen five to six hours later. Given that wheat is present in numerous food products, it is hard to eliminate it totally from the diet.

Cow’s milk allergy

Cow’s milk allergy is due to the proteins contained in the milk. It generally appears extremely early in infants and disappears in 90% of children after the age of three. To treat this allergy, cow’s milk proteins should be eliminated from the diet, but, for the child’s development, it is vital to replace them by other sources of proteins such as plant proteins (soya or rice).

For babies, Hypoallergenic substitute milk (HA milk) has been developed for babies. In HA milk, the proteins own been partially hydrolysed, i.e. they own been broken below into little pieces so that the immune system can no longer recognise them.

Egg allergy

Eggs, in specific certain proteins found in egg white, provoke allergic reactions more commonly seen in children than in adults. This allergy represents 30% of food allergies in children under fifteen but generally disappears around the age of four to seven. Egg allergy can, however, be permanent and accounts for 7% of food allergies in adults.

Peanut allergy

Peanut allergy is one of the most dangerous food allergies as it may own serious consequences., The incidence of peanut allergy is constantly on the rise and has doubled over the final ten years.

Unfortunately, this allergy does not vanish as children grow into adulthood.

Soya allergy

Soya often provokes allergic reactions in children. However, in most cases, children outgrow this allergy by the time they are of school age.

Nut allergy

Nuts such as walnuts, hazelnuts, almonds and pistachios are common food allergens. In most cases, nut allergy persists throughout the person’s life. As with most food allergies, treatment essentially entails avoiding nuts.

It is worth pointing out that a coconut is not considered a nut.

Fish and seafood allergy

Fish, crustaceans and molluscs are also responsible for food allergies which generally final throughout a person’s life. People who are allergic to fish are not necessarily allergic to seafood, and vice versa, but they are often allergic to several types of fish. As there is no treatment, the only solution is to avoid the allergen in question.

Sesame allergy

Sesame, a seed often found in Asian food and party snacks, contains proteins which can provoke an allergic reaction.

This form of allergy continues into adulthood and avoiding sesame seeds is the only effective treatment.