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Food Allergy Vs. Intolerance: How To Eat More Foods With IBS

How Common Are Food Allergies & Intolerances?

In Australia and New Zealand, food allergies affect;

  • 10% or 1 in 10 infants

  • 4-8% or 1 in 20 children aged up to 5 years old

  • About 2% or 2 in 100 adults

The most common triggers for food allergies are;

  • Wheat

  • Egg

  • Cow’s milk

  • Soy

  • Shellfish

  • Peanut

  • Tree nut

  • Sesame

  • Seafood

A child having a food allergy may not necessarily mean that it will continue into adulthood. Studies currently show that one third of adults under 30 years old, who have food allergies are food allergies that continued from childhood. Peanut allergies have been shown to be more likely to continue into adulthood with this occurring in 80% of people with a peanut allergy. Other food allergies that are more likely to continue into adulthood are tree nut, seed and seafood allergies. Whereas egg and shellfish allergies have been shown to be less likely to continue into adulthood.

There is currently limited information available about the prevalence of food intolerance’s. However, in 2011-12 the Australian Bureau of Statistics found that 17% of Australians aged over 2 years of age avoided eating a particular food because of a food allergy or intolerance. This is 3.7 million people in Australia.

Is Food Allergy Increasing?

This is question that I get asked quiet often and is an area where extra research is needed, and is currently being conducted, to be able to fully understand.

In Australia, the USA and UK hospital admissions have more than doubled for anaphylaxis, which is a severe type allergic reaction, in the past 10 years. In Australia, hospital admissions due to anaphylaxis related to food allergies in infants and children up to 4 years old is even greater and is five times higher than it was 10 years ago.

As I mentioned above, we currently don’t have any clear answers or information about why the prevalence of food allergies in increasing, particularly in children, however there are a number of suggested possibilities which include;

  • Waiting or delaying introducing food containing known food allergens such as peanuts and egg.

  • The way that foods are processed. For example, boiled peanuts compared to roasted peanuts.

  • The hygiene hypothesis. This suggests that a higher risk of developing a food allergy is associated with a lower exposure to infections during early childhood.

  • The way that we were born, caesarean section vs vaginal birth, as this impacts on the amount and diversity of the different types of bacteria in our gut microbiome. The diversity of gut bacteria is lower in infants born via caesarean section and the composition of their gut microbiome is different to those born vaginally. Vaginal births are associated with a lower risk of not only food allergies, but also eczema and asthma.

What is a Food Allergy?

A food allergy is when our immune system reacts to a food protein that the body wrongly thinks is harmful which causes a person to have a reaction and get symptoms. There are different types of food allergies which can cause different reactions. Some reactions can happen quickly and usually occur within 30 minutes, however, can also occur up to 2 hours of eating a particular food. This is known as an IgE-mediated food allergy and symptoms can include;

  • Hives

  • Swelling of the lips, tongue, throat, face and eyes

  • Stomach pain

  • Vomiting

  • Difficulty breathing and dizziness

  • Anaphylaxis

Some symptoms can be more delayed and can occur between 2 hours and 2 days after consuming a food. These reactions involve a different part of the immune system and are known as non-IgE mediated food allergies. It’s important to note that non-IgE medicated food allergy reactions can have both an immediate and delayed onset. Symptoms from this type of reaction usually involve the skin, stomach and digestive system and can include;

  • Nausea

  • Vomiting

  • Diarrhoea

  • Constipation

  • Skin reactions such as eczema

Types of Allergic Reactions to Food

Most people in Australia aren’t aware of the signs and symptoms of food allergy or that there are even different types of symptoms and reactions that people can have.

Although symptoms of a food allergy are usually obvious, it is really important to know the difference between a mild to moderate and severe allergic reactions as these can be life-threatening. These types of allergic reactions are common in Australia and New Zealand.

Mild to Moderate Reactions

Symptoms of a mild to moderated food allergy include;

  • Stomach pain

  • Vomiting

  • Hives or welts on the skin

  • Swelling of the lips, face or eyes

Anaphylaxis (Severe) Reactions

Anaphylaxis can be a life-threating reaction to a food allergen, and it should always be treated as a medical emergency. Anaphylaxis can be prevented by avoiding any food or foods that people know have an allergen in them and immediately administering adrenaline via an autoinjector if a reaction occurs. It is really important to know that not all people with food allergies will have an anaphylactic reaction.

Symptoms of anaphylaxis include;

  • Difficulty breathing or noisy breathing

  • Persistent cough or wheezing

  • Swelling of the tongue

  • Swelling or tightness in the throat

  • Finding it hard to talk or speaking with a hoarse voice

  • Ongoing dizziness and/or collapse

  • Paleness or limpness in young children

What is a Food Intolerance?

A food intolerance is not the same as a food allergy as a person’s reaction or symptoms caused by a food intolerance does not involve the immune system and are rarely life-threatening. A food intolerance is when a person cannot properly digest or fully break down and absorb certain foods. The most common food intolerance is lactose which is found in dairy foods.

There is a wide range of symptoms to food intolerance’s which are individual to each person. Symptoms can occur quickly or can also be delayed. Symptoms usually involve the stomach and digestive system and can include;

  • Bloating

  • Diarrhoea

  • Excessive wind

  • Stomach cramps

What are Food Chemicals?

Chemical sensitivities or intolerances are due to naturally occurring chemicals found in foods and include salicylates, amines, and glutamate and food additives. When ingested these chemicals cause reactions by irritating nerve endings in different parts of the body which leads to symptoms. These symptoms can be different in each person. These can include;

  • Bloating

  • Nausea

  • Stomach discomfort or pain

  • Diarrhoea

  • Headaches and migraines

  • Hives and swelling

  • Sinus trouble

  • Mouth ulcers

How an Elimination Diet Can Help

Determining the dietary triggers to your food allergies or intolerance’s is incredibly important. This will allow you to know which foods you can and cannot eat safely and which foods are likely to trigger your symptoms. It will also allow you to avoid unnecessarily restricting foods from your diet.

Managing a food allergy or intolerance may involve a temporary elimination diet. This is the only reliable way to confirm if diet is playing a role in your symptoms. This can be a big adjustment to your current diet and eating habits and may seem difficult and overwhelming at first. You may feel that meals times become more complicated or that eating out is no longer fun. However, you can relax! There are so many easy strategies that an Accredited Practising Dietitian (APD) will be able to provide you with so that you can still enjoy your activities and have pleasure from eating.

It is very important to remember that an elimination diet should only be completed under the supervision on an APD and only for a short amount of time. This is due to the fact that people following a restrictive diet, such as an elimination diet, are more at risk of nutrient deficiencies. An APD will provide you with appropriate substitutes to your favourite foods while ensuring you are getting all the nutrition you need with a healthy, balanced diet and a wide variety of foods.


Are you ready to break free from bloating, constipation or diarrhoea and start taking control of your IBS? CLICK HERE to book a Complementary Strategy Call with me to get started and let's create a nutrition plan that helps you feel confident in your food choices so you can so you can finally find lifetime relief from your IBS!



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