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.

After several highly publicised alleged murders of women in Australia, the Albanese government this week pledged more than A$925 million over five years to address men’s violence towards women. This includes up to $5,000 to support those escaping violent relationships.

However, to reduce and prevent gender-based and intimate partner violence we also need to address the root causes and contributors. These include alcohol and other drugs, trauma and mental health issues.

Why is this crucial?

The World Health Organization estimates 30% of women globally have experienced intimate partner violence, gender-based violence or both. In Australia, 27% of women have experienced intimate partner violence by a co-habiting partner; almost 40% of Australian children are exposed to domestic violence.

By gender-based violence we mean violence or intentionally harmful behaviour directed at someone due to their gender. But intimate partner violence specifically refers to violence and abuse occurring between current (or former) romantic partners. Domestic violence can extend beyond intimate partners, to include other family members.

These statistics highlight the urgent need to address not just the aftermath of such violence, but also its roots, including the experiences and behaviours of perpetrators.

What’s the link with mental health, trauma and drugs?

The relationships between mental illness, drug use, traumatic experiences and violence are complex.

When we look specifically at the link between mental illness and violence, most people with mental illness will not become violent. But there is evidence people with serious mental illness can be more likely to become violent.

The use of alcohol and other drugs also increases the risk of domestic violence, including intimate partner violence.

About one in three intimate partner violence incidents involve alcohol. These are more likely to result in physical injury and hospitalisation. The risk of perpetrating violence is even higher for people with mental ill health who are also using alcohol or other drugs.

It’s also important to consider traumatic experiences. Most people who experience trauma do not commit violent acts, but there are high rates of trauma among people who become violent.

For example, experiences of childhood trauma (such as witnessing physical abuse) can increase the risk of perpetrating domestic violence as an adult.

Early traumatic experiences can affect the brain and body’s stress response, leading to heightened fear and perception of threat, and difficulty regulating emotions. This can result in aggressive responses when faced with conflict or stress.

This response to stress increases the risk of alcohol and drug problems, developing PTSD (post-traumatic stress disorder), and increases the risk of perpetrating intimate partner violence.

How can we address these overlapping issues?

We can reduce intimate partner violence by addressing these overlapping issues and tackling the root causes and contributors.

The early intervention and treatment of mental illness, trauma (including PTSD), and alcohol and other drug use, could help reduce violence. So extra investment for these are needed. We also need more investment to prevent mental health issues, and preventing alcohol and drug use disorders from developing in the first place.

Preventing trauma from occuring and supporting those exposed is crucial to end what can often become a vicious cycle of intergenerational trauma and violence. Safe and supportive environments and relationships can protect children against mental health problems or further violence as they grow up and engage in their own intimate relationships.

We also need to acknowledge the widespread impact of trauma and its effects on mental health, drug use and violence. This needs to be integrated into policies and practices to reduce re-traumatising individuals.

How about programs for perpetrators?

Most existing standard intervention programs for perpetrators do not consider the links between trauma, mental health and perpetrating intimate partner violence. Such programs tend to have little or mixed effects on the behaviour of perpetrators.

But we could improve these programs with a coordinated approach including treating mental illness, drug use and trauma at the same time.

Such “multicomponent” programs show promise in meaningfully reducing violent behaviour. However, we need more rigorous and large-scale evaluations of how well they work.

What needs to happen next?

Supporting victim-survivors and improving interventions for perpetrators are both needed. However, intervening once violence has occurred is arguably too late.

We need to direct our efforts towards broader, holistic approaches to prevent and reduce intimate partner violence, including addressing the underlying contributors to violence we’ve outlined.

We also need to look more widely at preventing intimate partner violence and gendered violence.

We need developmentally appropriate education and skills-based programs for adolescents to prevent the emergence of unhealthy relationship patterns before they become established.

We also need to address the social determinants of health that contribute to violence. This includes improving access to affordable housing, employment opportunities and accessible health-care support and treatment options.

All these will be critical if we are to break the cycle of intimate partner violence and improve outcomes for victim-survivors.

The National Sexual Assault, Family and Domestic Violence Counselling Line – 1800 RESPECT (1800 737 732) – is available 24 hours a day, seven days a week for any Australian who has experienced, or is at risk of, family and domestic violence and/or sexual assault.

If this article has raised issues for you, or if you’re concerned about someone you know, call Lifeline on 13 11 14. In an emergency, call 000.

Siobhan O’Dean, Postdoctoral Research Associate, The Matilda Centre for Research in Mental Health and Substance Use, University of Sydney; Lucinda Grummitt, Postdoctoral Research Fellow, The Matilda Centre for Research in Mental Health and Substance Use, University of Sydney, and Steph Kershaw, Research Fellow, The Matilda Centre for Research in Mental Health and Substance Use, University of Sydney

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