Top 10 Most Common Food Allergies

The 10 most common allergenic foods are wheat, peanuts, tree nuts, shellfish, eggs, milk, fish, soy, sesame seeds and lupin.
June 28, 2016

Food allergies are serious illnesses and can cause varying reactions depending on the severity.

Approximately 2 percent of all adults suffer from a food allergy, 10 percent of infants under one and 4 to 8 percent of children up to five years of age. Many children grow out of their food allergies; however, allergies to tree nuts, peanuts, shellfish or seeds are more often lifelong conditions.

The 10 most common allergenic foods are wheat, peanuts, tree nuts, shellfish, eggs, milk, fish, soy, sesame seeds and lupin. Together they make up approximately 90 percent of all food allergies and vary from mild to life-threatening.

An intolerance is different from an allergy because a food allergy affects the sufferer's immune system, whereas an intolerance is an adverse reaction to a particular type of food. Although they both indicate sensitivity to food, an allergy can be life-threatening while an intolerance is most likely not.

Anyone preparing food, whether in a business or at home, should always practise a high level of food safety. Carefully knowing what each ingredient is made up of and informing those eating the food of all ingredients, is vital to ensure that people do not become ill.

10 most common food allergens in Australia

Different countries have different food labelling laws and in Australia, any product that contains any of the potential allergens on this list must have them clearly listed. Sulphites, too often added to food as a preservative, must also be printed on food labels.

Wheat

Wheat contains the protein gluten which people who suffer from the coeliac disease are allergic to. In many cases, a person suffering from the coeliac disease can tolerate rice but not other wheat-related grains such as oats, rye or barley. Currently, there is no cure for the coeliac disease and those who suffer from it are typically advised to refrain from eating foods that contain gluten.

If gluten is ingested, a person who is allergic to it can experience various symptoms, ranging from mild to life-threatening. They can include:

  • Inflammation in the abdomen and bowel, which is often painful
  • Diarrhoea, bloating and cramping
  • Mouth ulcers
  • Muscle pains
  • Skin irritations

If nutrients are not properly absorbed into the intestines due to coeliac disease, a person’s condition can worsen. Weight loss and/or anaemia can often result from an allergy to gluten. Also, because many nutrients aren’t being absorbed into the body, vitamin and nutrient deficiencies are often a result; such as vitamin D, calcium, zinc, selenium and copper just to name a few.

The coeliac disease also leads to a higher risk of suffering from other conditions such as lymphomas, dermatitis and/or pregnancy complications.

Peanuts

Despite the misleading name, peanuts are actually classified as legumes and not nuts. They contain many proteins that may trigger an allergic reaction and are common ingredients in many cuisines and pre-made products, such as satay sauces.

An allergic reaction to peanuts can happen within minutes or up to several hours after eating foods containing peanuts. Symptoms vary from person to person, and may progress from mild to severe. A person experiencing a peanut allergy may have any one or a combination of these symptoms:

  • Skin irritations and rashes
  • Abdominal pain, nausea and vomiting
  • Itchy mouth, throat or eyes
  • Swelling of the throat, tongue and lips
  • Shortness of breath
  • Anxiety or distress
  • Anaphylactic reactions – in severe cases

Severe reactions to peanuts can occur after very minimal contact, such as ingestion of trace amounts or skin contact, so it is very important that food handlers are not just careful with the ingredients and labelling of food, but also careful that they do not cause accidental cross-contamination.

The labelling laws for peanuts are very strict, including "may contain" statements, and many schools have also completely banned peanuts and the products made from them as a safety precaution.

Tree Nuts

Tree nuts, or simply "nuts", are one of the most common food allergies worldwide. Tree nut allergies are distinct from peanut allergy, as peanuts are legumes, whereas tree nuts are hard-shelled nuts. 

Tree nuts include almonds, Brazil nuts, cashews, hazelnuts, pecans, pistachios, chestnuts and walnuts. An allergy to one tree nut does not necessarily mean an individual is allergic to other tree nuts, but certain tree nuts are closely related, including cashew with pistachio and pecan with walnut. Many nut allergy sufferers avoid all tree nuts, just to be safe.  

Although nut allergies are more often found in children, they can appear for the first time in adults. Nut allergies can cause symptoms that range from mild to fatal and include:

  • Skin irritations and rashes
  • Abdominal pain, nausea and vomiting
  • Itchy mouth, throat or eyes
  • Swelling of the throat, tongue and lips
  • Shortness of breath
  • Anaphylactic reactions – in severe cases

As with peanuts, tree nuts can cause severe allergic reactions from very minimal contact with the allergen, so food handlers must:

  • be knowledgeable about ingredients in the foods they sell
  • be able to advise customers about foods to avoid
  • be trained to effectively communicate allergy requests to the kitchen, management and other members of staff
  • take all reasonable measures to prevent cross-contamination

Labelling laws for nuts are very strict and you will often see labels that say ‘may contain traces of nuts’ even if nuts are not one of the listed ingredients. The carrying of an epinephrine auto-injector (EpiPen) is also often recommended, which is used to treat an anaphylactic reaction.

Shellfish

Of the crustacean shellfish that can cause an allergic reaction, the most likely to be eaten by humans are prawns, crabs, lobsters, oysters, abalone and shrimps. In some cases, snails, molluscan shellfish, mites, dust and cockroaches can also affect those who suffer from a shellfish allergy, some of which simply by coming in contact with them.

The symptoms of an allergy to shellfish can vary depending on the severity and can include:

  • Tingling in the mouth
  • Nausea, vomiting and diarrhoea
  • Skin irritations
  • Dizziness and fainting
  • Throat swelling and breathing difficulty
  • Drop in blood pressure and rapid pulse
  • Anaphylaxis

Like many other food allergies, there is currently no cure for an allergy to shellfish and abstaining from consumption and carrying of an epinephrine (EpiPen) are most often recommended.

Food handlers should be very careful about cross-contamination when it comes to shellfish because just a trace of shellfish can be all it takes to cause someone a serious reaction. Properly washing hands and utensils after touching different types of food are as important as properly labelling all ingredients in food.

Eggs

Although eggs are a fundamental ingredient in many kitchens and meals, they are also responsible for a range of allergic reactions. Generally, it is hen’s eggs that mainly affect those who suffer from an egg allergy. Like some other allergies, an allergy to eggs mainly affects young children and is often outgrown after the child’s first six years.

Reactions to egg allergies often occur in the digestive system and symptoms can vary and include:

  • Skin inflammation and hives
  • Sneezing and nasal congestion
  • Abdominal pain and diarrhoea
  • Nausea and vomiting
  • Coughing, shortness of breath
  • Anaphylaxis – in some cases

Medical professionals usually recommend avoiding the ingestion of eggs or products containing egg, which is not necessarily an easy task. In actual fact, eggs are widely used as not just an ingredient in foods, but medicines and cosmetics as well. This makes it very easy for someone who suffers from an allergy to eggs to accidentally come into contact with the protein.

Milk

An allergy to milk is one of the more frequent food allergies worldwide and is reportedly the highest cause of food allergy in infants. Like eggs, an allergy to milk affects more children than adults and is often outgrown after a child reaches 6 years of age.

People who suffer from an allergy to milk are likely affected by either the lactose or the milk proteins, though in some cases both. A milk allergy can also cause the sufferer to have difficulty gaining weight or height. Some of the common symptoms of a milk allergy are:

  • Skin irritations
  • Abdominal pain and vomiting
  • Diarrhoea – which can contain blood
  • A runny nose, coughing and sneezing
  • Anaphylaxis – in some cases

People who suffer from a milk allergy may be able to use a substitute, for example, soymilk or almond milk. Avoiding milk altogether is relatively difficult because of the high number of products that contain it. Food handlers need to be very clear when labelling the ingredients of their food and also careful not to cross-contaminate.

Fish

Fish allergies are more common in populations with a high rate of seafood consumption and they primarily occur in adolescents and adults. It is estimated that approximately 1 per cent of the world's population suffers from some form of seafood allergy.

Symptoms of an allergy to fish can vary and often depend on the type of fish ingested, some symptoms are:

  • Skin Irritations
  • Swelling of the throat, mouth and nose
  • Vomiting and diarrhoea
  • Breathing difficulties
  • A severe drop in blood pressure
  • Anaphylaxis – in some cases

People that are allergic to fish can also be allergic to shellfish and vice versa. In some instances, fumes are all it takes to cause either an instantaneous or delayed reaction. Fish is a very commonly used food and is often used in stocks and dressings, which can make it difficult to spot. This means it is more essential that food handlers practise a high level of food safety and disclose every ingredient they use to the person eating their food.

Soy

Unlike many of the other most common food allergens, an allergy to soy is often more uncomfortable than life-threatening. If a severe reaction does occur, it is likely that the person also suffers from asthma or another allergy.

An allergy to soy / soya refers to soybeans, which are a member of the legume family, and does not necessarily mean that the sufferer will also be allergic to other legumes, peanuts for example.

The symptoms of a soy allergy can be:

  • Tingling in the mouth
  • Nausea, vomiting and diarrhoea
  • Skin irritations
  • Swelling of the lips, face, throat or tongue
  • Breathing difficulty
  • Skin redness

Soybeans and other legumes are widely used in cooking and can easily go unnoticed, which makes them particularly dangerous for those allergic to them. Soymilk is often used in coffee businesses and cross-contamination with other milk can be dangerous for those with a soy allergy. Although allergic reactions to soy are most likely non life-threatening, precautions must still be undertaken to minimise the risk of occurrence.

Sesame Seeds

Sesame seeds are especially potent when it comes to food allergens and are most often a lifelong allergy. An allergy to sesame seeds is also particularly difficult to control as the food label does not always specifically say sesame seeds. Other names indicate the presence of sesame seeds; for example, sim sim, benne or gingelly seeds. Both the people suffering from sesame seed allergies and food handlers need to be aware of each different name that can indicate the presence of sesame seeds.

Sesame seeds are tiny and it doesn’t take many to cause an allergic reaction. Some of the symptoms can be:

  • Skin irritations and rashes
  • Abdominal pain, nausea, vomiting and diarrhoea
  • Itchy mouth, throat or eyes
  • Swelling of the face, nose or mouth
  • Shortness of breath
  • Anaphylactic reactions – in severe cases

Ground sesame seeds are used in a multitude of different products including – dips, biscuits, bread, sauces, muesli, processed meats, chutneys, confectionary and countless Asian foods. Due to the high number of foods that contain sesame seeds is it essential that the correct ingredients are written on the label and/or menu.

Also like other food allergies, food handlers must ensure that they properly wash their hands, and must clean and sanitise utensils and any other equipment or surfaces that come in contact with food.

Lupin

Lupin is a legume that is more frequently consumed and used in the Mediterranean, especially in the form of lupin flour. Lupin allergy is an emerging food allergy, with variable prevalence rates in different geographical regions. It is more prevalent in Mediterranean countries and in Australia, and less prevalent in North America and Northern Europe.

Allergic reactions to lupin cause similar symptoms seen with other food allergens and may include:

  • Skin irritations / hives
  • Itchy mouth, throat or eyes
  • Swelling of the face, tongue or throat
  • Abdominal pain, nausea or vomiting
  • Runny nose or watery eyes
  • Shortness of breath, coughing or wheezing
  • Anaphylactic reactions – in severe cases

Allergic reactions to lupin often occur as a result of ingestion of commercial products containing ‘hidden’ lupin, such as gluten-free pasta products. Some people who are allergic to peanuts may also be allergic to lupin, as there is a high level of cross-reactivity between the two legumes, so be sure to check with a customer who discloses a peanut allergy if foods containing lupin are OK for them to eat. 

Food allergies are an important food safety issue

Food allergies should always be treated very seriously and the utmost care must be taken to ensure the risk of any reactions is minimal. Food businesses must clearly outline all ingredients in their dishes and customers should always inform the business if they suffer from a food allergy.

Food Safety Supervisors are responsible for ensuring that a high level of food safety is maintained and also that there is a reduced risk of illness resulting from consuming anything produced by the restaurant.

If you think that you or someone else are suffering from an allergic reaction to any food, seek medical care immediately.

This public health information was produced and distributed by the Australian Institute of Food Safety Foundation.