If you didn’t have food allergies as a child, is it possible to develop them as an adult? The short answer is yes. But the reasons why are much more complicated.

Preschoolers are about four times more likely to have a food allergy than adults and are more likely to grow out of it as they get older.

It’s hard to get accurate figures on adult food allergy prevalence. The Australian National Allergy Council reports one in 50 adults have food allergies. But a US survey suggested as many as one in ten adults were allergic to at least one food, with some developing allergies in adulthood.

What is a food allergy

Food allergies are immune reactions involving immunoglobulin E (IgE) – an antibody that’s central to triggering allergic responses. These are known as “IgE-mediated food allergies”.

Food allergy symptoms that are not mediated by IgE are usually delayed reactions and called food intolerances or hypersensitivity.

Food allergy symptoms can include hives, swelling, difficulty swallowing, vomiting, throat or chest tightening, trouble breathing, chest pain, rapid heart rate, dizziness, low blood pressure or anaphylaxis.

IgE-mediated food allergies can be life threatening, so all adults need an action management plan developed in consultation with their medical team.

Here are four IgE-mediated food allergies that can occur in adults – from relatively common ones to rare allergies you’ve probably never heard of.

1. Single food allergies

The most common IgE-mediated food allergies in adults in a US survey were to:

• shellfish (2.9%)
• cow’s milk (1.9%)
• peanut (1.8%)
• tree nuts (1.2%)
• fin fish (0.9%) like barramundi, snapper, salmon, cod and perch.

In these adults, about 45% reported reacting to multiple foods.

This compares to most common childhood food allergies: cow’s milk, egg, peanut and soy.

Overall, adult food allergy prevalence appears to be increasing. Compared to older surveys published in 2003 and 2004, peanut allergy prevalence has increased about three-fold (from 0.6%), while tree nuts and fin fish roughly doubled (from 0.5% each), with shellfish similar (2.5%).

While new adult-onset food allergies are increasing, childhood-onset food allergies are also more likely to be retained into adulthood. Possible reasons for both include low vitamin D status, lack of immune system challenges due to being overly “clean”, heightened sensitisation due to allergen avoidance, and more frequent antibiotic use.

2. Tick-meat allergy

Tick-meat allergy, also called α-Gal syndrome or mammalian meat allergy, is an allergic reaction to galactose-alpha-1,3-galactose, or α-Gal for short.

Australian immunologists first reported links between α-Gal syndrome and tick bites in 2009, with cases also reported in the United States, Japan, Europe and South Africa. The US Centers for Disease Control estimates about 450,000 Americans could be affected.

The α-Gal contains a carbohydrate molecule that is bound to a protein molecule in mammals.

The IgE-mediated allergy is triggered after repeated bites from ticks or chigger mites that have bitten those mammals. When tick saliva crosses into your body through the bite, antibodies to α-Gal are produced.

When you subsequently eat foods that contain α-Gal, the allergy is triggered. These triggering foods include meat (lamb, beef, pork, rabbit, kangaroo), dairy products (yoghurt, cheese, ice-cream, cream), animal-origin gelatin added to gummy foods (jelly, lollies, marshmallow), prescription medications and over-the counter supplements containing gelatin (some antibiotics, vitamins and other supplements).

Tick-meat allergy reactions can be hard to recognise because they’re usually delayed, and they can be severe and include anaphylaxis. Allergy organisations produce management guidelines, so always discuss management with your doctor.

3. Fruit-pollen allergy

Fruit-pollen allergy, called pollen food allergy syndrome, is an IgE-mediated allergic reaction.

In susceptible adults, pollen in the air provokes the production of IgE antibodies to antigens in the pollen, but these antigens are similar to ones found in some fruits, vegetables and herbs. The problem is that eating those plants triggers an allergic reaction.

The most allergenic tree pollens are from birch, cypress, Japanese cedar, latex, grass, and ragweed. Their pollen can cross-react with fruit and vegetables, including kiwi, banana, mango, avocado, grapes, celery, carrot and potato, and some herbs such as caraway, coriander, fennel, pepper and paprika.

Fruit-pollen allergy is not common. Prevalence estimates are between 0.03% and 8% depending on the country, but it can be life-threatening. Reactions range from itching or tingling of lips, mouth, tongue and throat, called oral allergy syndrome, to mild hives, to anaphylaxis.

4. Food-dependent, exercise-induced food allergy

During heavy exercise, the stomach produces less acid than usual and gut permeability increases, meaning that small molecules in your gut are more likely to escape across the membrane into your blood. These include food molecules that trigger an IgE reaction.

If the person already has IgE antibodies to the foods eaten before exercise, then the risk of triggering food allergy reactions is increased. This allergy is called food-dependent exercise-induced allergy, with symptoms ranging from hives and swelling, to difficulty breathing and anaphylaxis.

Common trigger foods include wheat, seafood, meat, poultry, egg, milk, nuts, grapes, celery and other foods, which could have been eaten many hours before exercising.

To complicate things even further, allergic reactions can occur at lower levels of trigger-food exposure, and be more severe if the person is simultaneously taking non-steroidal inflammatory medications like aspirin, drinking alcohol or is sleep-deprived.

Food-dependent exercise-induced allergy is extremely rare. Surveys have estimated prevalence as between one to 17 cases per 1,000 people worldwide with the highest prevalence between the teenage years to age 35. Those affected often have other allergic conditions such as hay fever, asthma, allergic conjunctivitis and dermatitis.

Allergies are a growing burden

The burden on physical health, psychological health and health costs due to food allergy is increasing. In the US, this financial burden was estimated as $24 billion per year.

Adult food allergy needs to be taken seriously and those with severe symptoms should wear a medical information bracelet or chain and carry an adrenaline auto-injector pen. Concerningly, surveys suggest only about one in four adults with food allergy have an adrenaline pen.

If you have an IgE-mediated food allergy, discuss your management plan with your doctor. You can also find more information at Allergy and Anaphylaxis Australia.

Clare Collins, Laureate Professor in Nutrition and Dietetics, University of Newcastle

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Around one in six Australians has some form of hearing loss, ranging from mild to complete hearing loss. That figure is expected to grow to one in four by 2050, due in a large part to the country’s ageing population.

Hearing loss affects communication and social engagement and limits educational and employment opportunities. Effective treatment for hearing loss is available in the form of communication training (for example, lipreading and auditory training), hearing aids and other devices.

But the uptake of treatment is low. In Australia, publicly subsidised hearing care is available predominantly only to children, young people and retirement-age people on a pension. Adults of working age are mostly not eligible for hearing health care under the government’s Hearing Services Program.

Our recent study published in the journal Ear and Hearing showed, for the first time, that working-age Australians from lower socioeconomic backgrounds are at much greater risk of hearing loss than those from higher socioeconomic backgrounds.

We believe the lack of socially subsidised hearing care for adults of working age results in poor detection and care for hearing loss among people from disadvantaged backgrounds. This in turn exacerbates social inequalities.

Population data shows hearing inequality

We analysed a large data set called the Household, Income and Labour Dynamics in Australia (HILDA) survey that collects information on various aspects of people’s lives, including health and hearing loss.

Using a HILDA sub-sample of 10,719 working-age Australians, we evaluated whether self-reported hearing loss was more common among people from lower socioeconomic backgrounds than for those from higher socioeconomic backgrounds between 2008 and 2018.

Relying on self-reported hearing data instead of information from hearing tests is one limitation of our paper. However, self-reported hearing tends to underestimate actual rates of hearing impairment, so the hearing loss rates we reported are likely an underestimate.

We also wanted to find out whether people from lower socioeconomic backgrounds were more likely to develop hearing loss in the long run.

We found people in the lowest income groups were more than twice as likely to have hearing loss than those in the highest income groups. Further, hearing loss was 1.5 times as common among people living in the most deprived neighbourhoods than in the most affluent areas.

For people reporting no hearing loss at the beginning of the study, after 11 years of follow up, those from a more deprived socioeconomic background were much more likely to develop hearing loss. For example, a lack of post secondary education was associated with a more than 1.5 times increased risk of developing hearing loss compared to those who achieved a bachelor’s degree or above.

Overall, men were more likely to have hearing loss than women. As seen in the figure below, this gap is largest for people of low socioeconomic status.

Why are disadvantaged groups more likely to experience hearing loss?

There are several possible reasons hearing loss is more common among people from low socioeconomic backgrounds. Noise exposure is one of the biggest risks for hearing loss and people from low socioeconomic backgrounds may be more likely to be exposed to damaging levels of noise in jobs in mining, construction, manufacturing, and agriculture.

Lifestyle factors which may be more prevalent in lower socioeconomic communities such as smoking, unhealthy diet, and a lack of regular exercise are also related to the risk of hearing loss.

Finally, people with lower incomes may face challenges in accessing timely hearing care, alongside competing health needs, which could lead to missed identification of treatable ear disease.

Why does this disparity in hearing loss matter?

We like to think of Australia as an egalitarian society – the land of the fair go. But nearly half of people in Australia with hearing loss are of working age and mostly ineligible for publicly funded hearing services.

Hearing aids with a private hearing care provider cost from around A$1,000 up to more than $4,000 for higher-end devices. Most people need two hearing aids.

Lack of access to affordable hearing care for working-age adults on low incomes comes with an economic as well as a social cost.

Previous economic analysis estimated hearing loss was responsible for financial costs of around $20 billion in 2019–20 in Australia. The largest component of these costs was productivity losses (unemployment, under-employment and Jobseeker social security payment costs) among working-age adults.

Providing affordable hearing care for all Australians

Lack of affordable hearing care for working-age adults from lower socioeconomic backgrounds may significantly exacerbate the impact of hearing loss among deprived communities and worsen social inequalities.

Recently, the federal government has been considering extending publicly subsidised hearing services to lower income working age Australians. We believe reforming the current government Hearing Services Program and expanding eligibility to this group could not only promote a more inclusive, fairer and healthier society but may also yield overall cost savings by reducing lost productivity.

All Australians should have access to affordable hearing care to have sufficient functional hearing to achieve their potential in life. That’s the land of the fair go.

Mohammad Nure Alam, PhD Candidate in Economics, Macquarie University; Kompal Sinha, Associate Professor, Department of Economics, Macquarie University, and Piers Dawes, Professor, School of Health and Rehabilitation Sciences, The University of Queensland

This article is republished from The Conversation under a Creative Commons license. Read the original article.