When I was a child, I don’t remember knowing anyone with a food allergy. You’re probably the same. But now, especially if you’re a parent, I bet you know at least one allergic child, if not more. Schools are now in the practice of banning peanuts from lunches, and most teachers would have a stash of EpiPens in their desks. It’s estimated up to one in 10 infants has an allergic reaction to food.
What’s going on here? Why are food allergies increasing?
The answer, according to science, is: we’re not sure. There are a few theories in play, and lots of research going on.
One theory is the so-called “hygiene hypothesis”. Basically, this is the idea that we’re a bit too clean. Overzealous use of antibacterial products in our homes and not letting our wee ones get a bit dirty means their immune systems aren’t learning to react appropriately to foreign threats.
We need to be exposed to bugs, both good and bad, to develop our immunity. When we’re not, things can go haywire and we get allergic reactions.
There are other possible explanations, too. There’s an intriguing link between vitamin D levels and food allergies. Kids with the lowest levels of the “sunshine vitamin” are more likely to have food allergies. Researchers are exploring why this might be.
Kids with the lowest levels of the “sunshine vitamin” are more likely to have food allergies.
It’s also thought that stress and environmental pollutants might play a role.
It’s important to note that a true food allergy is different from an intolerance. Allergies are immune-system responses, and they can be life-threatening. Allergic reactions include things like wheezing, difficulty breathing, hives, and at the extreme end, anaphylaxis. They tend to happen straightaway after eating a particular food, or within a few minutes. Delayed reactions are rare, though food allergies can also trigger eczema in kids, which is a more delayed response.
Intolerances are generally milder and don’t cause allergic reactions, and the reactions they do cause are more likely to be delayed.
People with food allergies need to carefully and completely avoid the food they’re allergic to, even in tiny traces; whereas, with an intolerance, it’s likely you’ll be able to tolerate a little of that problematic food.
It’s interesting (and reassuring for parents who are dealing with the distress and stress of a child with a food allergy) that most kids with allergies to milk, egg, wheat or soy will outgrow the allergy by the time they’re around five. Other allergies – like peanut allergy – are more likely to stick around into adulthood.
Allergies can develop in adults, too, though this is more rare. It can even happen with foods we might have happily eaten before, such as shellfish.
Allergies can run in families. But that doesn’t automatically mean your child will have a food allergy if you do. It’s impossible to predict, right now, whether a child will inherit a parent’s food allergy or whether a sibling is more likely to also develop an allergy.
There’s recent evidence on peanut allergies which has led to the guidelines for introducing peanuts to infants being changed. It used to be thought we should delay giving potential allergens like peanuts to babies. Now, that advice has been reversed after a large Australian study found that giving peanuts (in the form of peanut butter, since nuts are a choking hazard) earlier rather than later really reduces the risk of peanut allergy in small children. The advice is to introduce peanuts to children as young as four to six months, if a baby is already eating solid foods, and if they are at high risk of having a peanut allergy. As always, seek the advice of your doctor or allergy specialist first!
There’s a similar bit of evidence around egg. Infants who were first given egg earlier (between four and six months, again) had significantly lower rates of food allergies than infants first given egg after six months. There’s a theory this might also be linked to vitamin D, since eggs are a source of that vitamin.
Food allergies – especially in children – can be stressful and difficult to manage, especially as kids get older and start to become more independent, spending time away from parents who might be used to keeping a watchful eye out for allergens. It can be worthwhile joining a support organisation such as Allergy New Zealand to stay connected to others and keep up with the latest advances regarding allergies. It also helps to have an understanding and knowledgeable medical practitioner on board.
If you suspect you or a family member has a food allergy, start at the doctor’s office and get referred for proper testing. This is not an area for self-diagnosis – the results of that could be fatal.