How Allergies Can Develop Over Time
Published: 25th October 2024 · Written by Donna Mastriani
Can allergies develop in adulthood? The short answer is yes. The standard narrative about allergies is that they primarily begin early in childhood and either resolve by the time we reach adulthood or else become much less severe.
But that’s not an accurate picture – allergies can develop in adults, worsen, or stay exactly the same. In fact, allergies appear to be on the rise due to a combination of genetic, environmental, and immunological factors.
Managing allergies requires an understanding of these causes and why allergies can worsen or develop late into adult life.
Why We Get Allergies?
What is an allergy? Allergies happen because your body flags an otherwise harmless substance, say pollen, foods, or animal dander, as a dangerous invader. As soon as it detects the “antigen” – a chemical marker – it launches a full-scale immune response. Histamine floods the bloodstream, and an allergic reaction occurs.
Allergies develop in the first place when a person is exposed to an allergen. Some people’s immune system is more trigger-happy than others, flagging the allergen and developing antibodies (IgE) in response. Then, when the allergen is present again, the reaction occurs – even if previously the person had no response.
Such a sensitisation reaction usually occurs in childhood – especially if the child isn’t exposed to a particular foodstuff. For example, peanut allergies may be increasing due to a lack of exposure to peanuts.
Common Adult Allergies
Food and environmental allergies aren’t the same. While the underlying mechanism is similar, environmental allergies are more likely to be seasonal, involve different symptoms, and are less severe. Food allergies may lead to anaphylaxis, a potentially deadly condition, while a pollen allergy does little more than cause a severe case of the sniffles.

According to the research, shellfish is the most common adult-onset food allergy. You can be 50 years or older and suddenly find you can no longer eat prawns safely.
Another potential cause is oral allergy syndrome (OAS), also known as pollen food allergy syndrome (PFAS). This condition results from cross-reactivity between pollen and certain foods. Individuals with specific types of hay fever may experience symptoms when consuming certain raw fruits and vegetables due to the similarity between pollen allergens and food proteins. These symptoms usually occur only with raw foods and are primarily localised to the mouth.
Other common adult allergies include:
- Seasonal Allergies. The most common adult-onset allergies are seasonal, triggered by pollen, ragweed, and other plant allergens that peak during certain times of the year, typically in the spring or fall.
- Pet Allergies. Owning a cat or dog can lead to developing allergies due to constant exposure to their dander (skin flakes that become airborne) and chemicals from their urine and saliva that adhere to the dander.
Why Can Allergies Develop in Adulthood?
The short answer is we don’t know. Some evidence points to the idea that a severe allergic reaction during childhood increases your likelihood of adult-onset allergies. Moreover, so-called “atopic” individuals, i.e., those with asthma, eczema, or hay fever (allergic rhinitis), are more at risk.
Symptoms may fade in such individuals before resurging due to one of these factors:
- Getting a pet for the first time.
- Moving to a new home or workplace.
- Little exposure to an allergen as a child.
- Lower immune function, e.g., being sick, pregnant, or immunocompromised.
Three of these factors have one thing in common – lack of exposure. When your body isn’t routinely exposed to certain allergens, a new exposure increases the chance it flags it as a threat.
However, even if you develop allergies as an adult, symptoms can still fade over time. As your immune function declines, so does its trigger-happy response to allergens.
Managing Allergy Symptoms
Managing allergies fall into two parts: diagnosing the culprit and managing allergy symptoms. The first part usually involves some kind of allergy test.
Allergy tests are often quite uncomfortable, requiring direct exposure to the allergen. Skin-prick tests, for example, involve the application of an allergen to your skin. If a reaction occurs, the allergy is confirmed.
However, there is another option – an IgE allergy test. Our Complete Body Test looks for 38 allergies (and 79 intolerances) by measuring levels of IgE antibodies specific to a particular allergen in the blood. It’s a simple, affordable, and non-invasive option.
Once you’ve diagnosed the cause, managing allergy symptoms requires eliminating the offending food or environmental culprit from your life. Depending on the severity of your reaction, you should carry either antihistamines or an adrenaline auto-injector (EpiPen) to counteract symptoms should you be exposed.
Get Tested with Life Lab Testing
So, can allergies develop over time? Yes! If you suspect you’ve developed an allergy, try the Complete Body Test. It’s the gold standard for home-to-lab testing. Simply provide a pinprick blood sample using the test kit and send it to our lab. You’ll receive your results within 1 week.
That’s not all – we also provide a free 30-minute nutritional therapist session to help you understand your results and place any lifestyle changes.
Buy the Complete Body Test today and take control of your health.
