Why I’m learning to question food allergy tests
In today’s episode of what I’ve learned in vet school, I wanted to look at food allergy tests.
Food allergies can feel confusing because the symptoms are often broad. Itching, ear inflammation, tummy signs, and skin changes can all make pawrents wonder if food is involved. But one thing I’m learning is that not every “allergy test” gives a clear answer.
Blood tests can give misleading results
Some blood tests look for IgE or IgG antibodies to food proteins. But antibodies in blood do not always mean the food is causing symptoms.
Antibodies can simply show exposure, not disease. A pet may have come into contact with a food protein before, but that does not automatically confirm that the food is the true trigger.
Food reactions can also involve gut and skin immune pathways that are not accurately captured by one blood result. This is why blood results can sometimes create more questions than answers.
Saliva and bioresonance tests are not reliable for diagnosis
A true food allergy involves the immune system reacting to food proteins. From what I’m learning, saliva and bioresonance tests are not reliable ways to diagnose this.
Saliva tests have not been shown to reliably match clinical food reactions. Bioresonance also does not measure recognised allergy pathways like antibodies, immune cells, or inflammation.
This matters because inaccurate results can lead to unnecessary food restrictions.
Why long allergy lists can be unhelpful
A long “allergy list” may create more confusion than clarity.
Some pets may end up avoiding many ingredients unnecessarily. This can make feeding harder without solving the real problem. Meanwhile, the true cause of the itch, ear infection, or tummy issue may still be missed.
This is one reason I’m learning that context matters so much. A test result should not be looked at in isolation.
Only an elimination diet can confirm a food allergy
Food allergy is not confirmed by finding a “suspicious” ingredient. It is confirmed when symptoms improve after that food is removed, then return when it is reintroduced.
That remove-and-rechallenge pattern is what helps identify a true trigger.
A food trial usually needs around 8 weeks, sometimes longer depending on the case. It takes time for the immune system and inflamed skin or gut to calm down. Itching, ear inflammation, or tummy signs may not resolve immediately, and your vet may adjust the duration based on your pet’s symptoms and response.
During a food trial, consistency matters. No sneaky treats, no table scraps, and no flavoured medications. It can also help to track itching, skin, ears, stool, and energy.
At Hara, this is why we care about clear ingredient lists and thoughtful formulation. Explore our small-batch treats if you are looking for transparent snacks to complement your pet’s routine, and always check with your vet before changing your pet’s diet.
This post reflects my personal experience as a vet student and is not professional veterinary advice.
0 comments