Over the past number of years, we have heard more and more about food allergies. According to the Government of Canada, people are more aware of food allergies and their risks than ever before. Schools and other facilities have guidelines regarding what foods one cannot eat on the premises, and products with allergen-free claims are in every grocery store. But why has this become a growing concern amongst Canadians? Has the number of people suffering from allergies always been the same and just awareness increasing? Or is something causing allergies in children more frequently?
Food is an integral part of life, and as a food lover, I am lucky that I don’t have any allergies, but I know people that face this life-threatening risk every day. It is vital to be food aware and careful with the safety of those around you that may have an allergy.
What is an Allergy?
Medically, the definition of an allergic reaction is an IgE-mediated response to an allergen (usually a food protein) and is very different from intolerance or sensitivity – food allergies can kill. Statistics show that 1 in 10 adults and 1 in 13 children have allergies. A recent report suggests that as many as 3.1 million Canadians have at least one food allergy, and allergies impact 1 in 2 households (Dalhousie University, Agri-Food Analytics Lab – AAL). Approximately every 10 minutes there is an emergency department visit for a food allergy episode in Canada.
Some of the most common food allergies include peanuts, tree nuts, eggs, milk, fish, shellfish, heat, soy, and sesame. Shellfish is the most common allergy for adults, followed by peanut and tree nuts. In children, it is eggs, milk, and peanuts. There are various reactions a person can have to an allergy, ranging from hives to respiratory issues and even cardiovascular responses. Anaphylaxis, a serious and rapid allergic reaction, may even cause death. (Those with allergies should carry an epinephrine auto-injector that contains life-saving medication like EpiPen.) According to Food Allergy Canada, most allergic reactions will happen in minutes, but some can occur hours after exposure.
Interestingly enough, allergies are more prevalent in developed countries like Canada, the United States, the United Kingdom, and Australia. Even more interesting is that they are on the rise in these countries. Studies in the UK have shown that hospital admissions for food allergies have increased by an astounding 500% since 1990.
Science Has Some Theories
So, what is causing the rise in food allergies? Science has some interesting theories. Firstly, they blame hygiene, otherwise referred to as the “hygiene hypothesis”. People in developed countries live in cleaner and more sanitized environments, and as a result, children are not getting as many infections. With fewer germs to fight, the immune system turns on things that, under normal circumstances, should be harmless, like food.
Another theory revolves around environmental factors. Studies have shown that the environment plays a significant role in the development and manifestation of allergic conditions in those people that are genetically predisposed. Pollution or airborne allergens like dust mites can aggravate allergic reactions resulting in asthma. With one allergy developing, the individual is more likely to develop additional allergic sensitization, including ones to food.
A third theory is a lack of vitamin D as we spend more time indoors and less time in the sun. The rate of vitamin D deficiency is thought to have doubled in just over ten years and can result in several auto-immune diseases and deficiencies. Studies have shown that vitamin D modulates genes in us that can potentially cause auto-immune diseases and allergies. In other words, vitamin D acts as our body’s protector.
One would think that genetics plays a role as well. In other words, if someone in your family has an allergy, you are more likely to have one as well. This is not always the case. Over 50% of children who develop allergies do not have a family history or a direct family member with a food allergy. In reality, no one is born with an allergy, they develop over time.
Allergies can start as early as infancy. An infant who is breastfeeding can have an allergic reaction to something in their mother’s diet. Studies in feeding guidelines, specifically the delayed introduction of certain foods, are under scrutiny as a possible reason for the ongoing rise of allergies amongst children. This theory, known as the “dual-allergen exposure hypothesis”, suggests that early exposure to food allergens can lead to tolerance. One such international clinical trial published in The New England Journal of Medicine (2015), the LEAP study, evaluated introducing peanuts for at-risk infants with a genetic history of allergies as early as 4 months of age. The study found that the risk of developing a peanut allergy dropped by 81%. The resulting data was so substantial that the U.S. Food and Drug Administration (FDA) and the National Institute of Allergy and Infectious Diseases (NIAID) formally support an early introduction of peanuts in an infant’s diet.
Finally, geographical location plays a fascinating part in allergies. EuroPrevall, a global research project funded by the European Union, looked at allergy patterns amongst various countries. They found that people seem to develop food allergies to the foods most commonly consumed in their region. For example, rice allergy is common in Eastern Asia and extremely rare in Canada (even though it is one of the first foods introduced to infants). Peanut allergies are common in Canada, the United States, and the United Kingdom but almost non-existent in Greece. Researchers acknowledge how important it is to study food allergies globally. Not only do people migrate, but so do their foods. We have adopted foreign cuisine, imported exotic products, and consumed new and exciting foods. Statistics list over 170 foods that can cause an allergic reaction. Could this be a result of the globalization of food?
Changing the Food Industry
Decades ago, manufacturers gave little regard to allergies. It was not economically viable to change production to accommodate 1% to 2% of the population. As a result of increased awareness and the number of people with food allergies (especially children), the food industry has changed. When someone in a family has a food allergy, the entire family usually follows that restricted diet. Furthermore, facilities ban products that may cause an allergic reaction. That 1% to 2% has grown exponentially, and food manufacturers have had to pay attention.
In Canada, Food and Drug Regulations require that most prepackaged foods include ingredients on the labels in decreasing order of proportion. Based on consultations with the medical community and allergy associations, labels must also indicate specific “priority” allergens. On a global basis, the Codex Alimentarius Commission has established a list of common allergenic foods, with manufacturing requirements established both nationally and internationally (the international standard for food safety is ISO 22000:2007). Food manufacturers implement these controls not only to avoid product recalls but also to protect their consumers.
Weird Food Allergies
In learning more and more about allergies, I came across some surprising ones. Most of us have heard about peanuts and shellfish, but listed below are six others that are strange but true.
- Red meat: Yes, that’s right. Although rare and difficult to identify, some people react to a sugar found in meats called alpha-galactose. The good news for them is that there are now so many options for a meat-free diet.
- Avocados: Did you know that the protein found in avocados is structurally similar to that found in natural rubber latex? This protein is what people will have an allergic reaction to, so if you are allergic to latex, steer clear away from avocados as well.
- Gelatin: Gelatin is a protein that forms when boiling the connective tissue in animals. Now that doesn’t sound too appetizing. Think of that the next time you eat gummy candies, marshmallows, and most of the processed items in your diet (including cereals).
- Mangoes: Mangoes, like avocados, are linked to latex allergies. Mangoes can also cross-react if someone is already allergic to apples, pears, celery, fennel, pistachios, or cashews.
- Sulfites: Sulfites, such as sulfur dioxide, are used as preservatives in various foods like vinegar, dried fruits, processed meats, condiments, and canned or frozen fruits and vegetables. More importantly, they are a component of wine and beer. If this is an allergy you suffer from, your only viable choice of drink is now sake.
- Hot dogs: Nitrates found in hot dogs are suspected to be responsible for this allergy, but with so many other chemicals used in their processing, one must wonder. It will remain a mystery until the end of time.
The Good News
As serious as allergies can be, there is good news. Studies have shown that even though the number of people with allergies is increasing, deaths have substantially decreased. Although it is probably a result of better healthcare, the availability of EpiPens, and better labeling and awareness, it is still a step in the right direction.
Remember, if someone you love has an allergy, there is hope. The future is promising. More and more clinical trials study the possibility of allergen immunotherapy and food desensitization. In the meantime, until we find a cure, the world of food offers a variety of alternate options that will be safe and delicious to eat.
To learn more about food allergies visit:
Canadian Society of Allergy and Clinical Immunology (CSACI)