Anyone can have an intolerance or allergic reaction to anything. Over on the Allergies/Asthma board, we get all sorts of allergies/intolerances and one thing I found is that the majority of the people there don't have an actual allergy to the product but the chemicals/antibiotics/hormones they inject into the animals. Once they change to a free range/organic product, their intolerances/allergic symptoms go away.
Oh and I absolutely adore beef products! I have never had any troubles digesting it but I know some people here just can't digest beef while flaring.