This is a complicated question to answer.
"Most" individuals with a peanut allergy can tolerate highly refined peanut oil because the allergy is to peanut protein and highly refined oils typically do not have any proteins left.
However "most" peanut allergic individuals avoid peanut oil because you can't ever know how refined it is. Even if it states refined on the bottle--there could still be a detectable amount of peanut protein left. Whether a reaction occurs depends upon the individual and how sensitive or allergic they are.
There are so many other oils available--why not try one of those rather than take the risk?
My son has a severe allergy, but is able to eat at chick fila, who uses peanut oil. Our allergist told us that there is a small number of patients who are unable to have peanut oil.
I cannot have any peanut whatsoever. Chick-fil-A always gives me rashes. We thought it was the chicken, but I never reacted the same with McDonald's. Then when my peanut allergy progressed to where I have asthma attacks from ingestion or breathing, we figured out it was the peanut oil.
We avoid peanut oil, it's just not worth the chance of a reaction.
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