You can develop an allergy at any age, to any food, despite having eaten that food without any prior symptoms. While allergies are most common among children (affecting 10 per cent of Aussie and Kiwi infants and only two to four per cent of Aussie and Kiwi adults), a study of 40,000 US adults found almost half of those living with allergies developed them after the age of 18.
So what is an allergy?
An allergy occurs when your immune system has an adverse reaction to a normally harmless substance, like food, pollen or dust mites and determines that the substance is a threat. This then causes a reaction in your body—usually in the form of hives, swelling or breathing symptoms.
Can you develop an allergy as an adult?
Yes you can. It is possible to develop food allergies (or other allergies) as you naturally progress through life. As you age, some researchers suggest that your immune system may weaken naturally, which may be why you’re suddenly struggling with that creamy milkshake or feeling itchy after some grilled fish. Certain events (like pregnancy or illness) can also compromise your immune system, which may trigger a new reaction.
Intolerance or allergy?
If your symptoms mainly involve the digestive system (like stomach or abdominal pain, bloating and gas) a few hours after eating certain foods, this is likely an intolerance. Like your body’s immune system, your digestive system can be affected as you age which may see you develop an intolerance later in life.
What are the symptoms of an allergy?
Unlike an intolerance, an allergy can be serious. Your symptoms would mainly involve an immune system response after eating or coming into contact with an allergen. Symptoms will appear quickly—usually within 20 minutes to 2 hours. They may start off mild, but progress rapidly. The most dangerous reactions (anaphylaxis) involve the respiratory and cardiovascular systems and are extremely serious. While more mild allergies may be treated by antihistamines (which appropriately enough, fight off the histamines released by the body) or other medication, severe allergic reactions which cause anaphylaxis may require more severe treatment—those with these types of allergies often carry an auto-injector or epipen with epinephrine (a type of adrenaline) in case they are accidentally exposed to allergens which may cause a life-threatening reaction for them. These types of medication can help balance the immune response in order to prevent this.
What can you be allergic to?
Different allergies are triggered by different types of food. If you are unsure about a possible allergy, doctors use skin prick tests or blood tests to verify reactions to a particular food, as well as to more common food allergens. Here are some examples of common food allergies or intolerances that you may encounter.
Gluten is a protein found in wheat, wheat varieties like spelt or farro, and is also found in rye, triticale, oats and barley. Unlike coeliac disease, gluten intolerance is often self-diagnosed as there are no tests to determine gluten sensitivity.
Tree nut and peanut allergies are among the most common allergies in adults, along with fish and shellfish. The most common triggers of food allergic reactions in childhood are peanuts, tree nuts, milk and egg. Other forms of nut allergy may include cashews, pecans or other types of nut.
Everyone is born with the enzyme lactase, which helps your body digest the lactose in foods. As you get older and your lactase production declines, you may find yourself suddenly struggling with high lactose dairy products like milk, and experience mild to severe symptoms like bloating, wind and diarrhoea if you have too much. This is another common allergy amongst young children, with many having a cow’s milk allergy which they often grow out of.