January 2021. About this episode: The debate on whether you need to activate nuts has been around for a while.…
Allergy in Australia
Allergy in Australia
Guest blog by Maria Said, CEO Allergy & Anaphylaxis Australia.
How common is food allergy in Australia?
Australia has one of the highest rates of food allergy in the world. Research indicates that in Australia, one in 10 infants (1), one in 20 children (aged 10-14 years) (2) and one in 50 adults have a food allergy (3).
Hospital presentations for anaphylaxis, triggered by food allergy, have noticeably increased in the past three decades. In the 14 years from 1998-2012, we saw a four-fold increase (4).
The most common food triggers are egg, cows’ milk (dairy), peanut, tree nuts, sesame, soy, wheat, fish and other seafood, but almost any food can cause an allergic reaction.
Some food allergies can be severe, causing life threatening reactions – known as anaphylaxis. Urgent medical attention and treatment with an adrenaline (epinephrine) injector is required.
Why are food allergies on the rise?
We’re not entirely sure why food allergy has increased so rapidly.
Current research suggests that it is related to a western lifestyle, the environment and a genetic predisposition as well as a number of other risk factors. These include:
- The hygiene hypothesis (5). This suggests that less exposure to infections in early childhood is associated with an increased risk of allergy. It is thought that exposure helps the immune system’s ability to tell the difference between harmful and harmless substances. Further research shows that the type of bacteria that the mother and infant are exposed to may alter the risk of developing allergic disease.
- Skin exposure to allergens (6). There is evidence that the use of moisturisers or creams containing food protein (eg. nut, dairy, oat) in infants with eczema and who have a damaged skin barrier can lead to development of food allergy. This low-dose exposure can sensitise infants through the skin rather than through the gut, increasing their risk of developing a food allergy.
- Methods of food processing (7). It is known that roasted peanuts are more allergenic than boiled peanuts. Peanut allergy is higher in countries such as Australia and USA where peanuts are roasted compared with Asia where peanuts are boiled.
- Vitamin D levels (8). Vitamin D is important for a healthy immune system. A deficiency in Vitamin D (via reduced sun exposure) has been linked to a higher risk of allergy. Studies have shown that countries further from the equator have higher admission rates for allergic reactions in children. Also, infants born in the autumn and winter months have a higher incidence of food allergy.
- Delayed introduction of allergenic foods (10). Recent studies have shown that a delay in the introduction of solid food (eg. peanut, egg) to babies after the age of 12 months can increase the chance of developing food allergies. It is now recommended that solid foods are introduced to babies around 6 months, not before 4 months, to help prevent food allergies developing.
Managing food allergies
While there is ongoing research to prevent and treat food allergies, there is currently no cure.
There have been significant advances in food allergy oral immunotherapy (OIT) as a potential treatment but safety, cost effectiveness, quality of life and long-term outcomes need to be further assessed before OIT becomes available outside of the medical research setting in Australia.
Managing a food allergy involves strict avoidance of the allergen, including always reading food labels and making known any allergies to those preparing food.
As risk of an allergic reaction cannot be eliminated, individuals (and their carers), must always be prepared for when an allergic reaction does occur. This means carrying an ASCIA Action Plan and, if prescribed, an injectable adrenaline which is the first line treatment for anaphylaxis.
Education on how to avoid triggers, how to respond in an emergency and regular reviews with a clinical immunology/allergy specialist are key.
Eating out with a food allergy
Most severe allergic reactions and the majority of deaths from food allergy happen outside of the home.
It’s vital that people living with a food allergy, clearly communicate their allergy to a food service provider and that their food allergy is taken seriously.
When travelling to foreign countries, or when eating in restaurants where English may not be the first language for staff, it can be difficult to clearly disclose a food allergy verbally. To help with this, Allergy & Anaphylaxis Australia (A&AA) has developed downloadable ‘Chef Cards’, which have been translated into 21 languages.
A chef card template can be accessed from the A&AA website and edited to include one’s allergens, and personalised, ready to be taken by a person with a food allergy to restaurants and other food outlets to assist in communicating allergen information.
More information and resources on food allergy:
- Osborne NJ, Koplin JJ, et al. Prevalence of challenge proven IgE-mediated food allergy using population-based sampling and predetermined challenge criteria in infants. J Allergy Clin Immunol. 2011.
- Sasaki M, Koplin JJ, et al. Prevalence of clinic-defined food allergy in early adolescence: The School Nuts study. J Allergy Clin Immunol. 2017.
- Tang MLK, Mullins RJ. Food allergy: is prevalence increasing? IMJ. 2017.
- Mullins RJ, Dear KBG, Tang ML. Time trends in Australian hospital anaphylaxis admissions 1998/9 to 2011/12. J Allergy Clin Immunol. 2015.
- Ashley S, Dang T, et al. Food for thought: progress in understanding the causes and mechanisms of food allergy. Curr Opin Allergy Clin Immunolo. 2015.
- Karmaus W, Ewart SL, et al, Filaggrin loss of function mutations are associated with food allergy in childhood and adolescence. J Allergy Clin Immunol. 2014.
- Verhoeckx KC, Vissers YM, et al. Food processing and allergenicity. Food Chem Toxicol. 2015.
- Allen KJ, Koplin JJ, et al. Vitamin D deficiency is associated with challenge-proven food allergy in infants. J Allergy Clin Immunol. 2013.
- Du Toit G, Roberts G, et al. LEPA Study Team. Randomized control trial of peanut consumption in infants at risk for peanut allergy. N Engl J Med. 2015.
- ASCIA. Infant feeding advice https://www.allergy.org.au/images/pcc/ASCIA_Guidelines_infant_feeding_and_allergy_prevention.pdf
Published December 15, 2020