Over the years, I have had some quite serious reactions to foods containing the antioxidants BHA and BHT. I have been advised that the reason for my particular sensitivity is genetic deficiency of an important protease inhibitor protein. I have a 70 percent deficiency of Alpha1-protease inhibitor (aka alpha1-antitrypsin, alpha1-serpin).

PI deficiency is the most common genetic disorder, affecting about 15 percent of Australians (The pi gene is co-dominant, with about 1 in 400 Australians carrying the severe deficiency). The protease inhibitor is a down-regulator of inflammatory processes associated with a number of metabolic pathways, particularly the myeloperoxidase (MPO) pathway. Consequently, I have adverse reactions with exposure to a number of substances at levels that are generally considered to be safe for persons with the normal pi genotype.

I am very concerned about the wider use of these substances as food additives, particularly where the use of additive is not described on the product packaging. – reader from NSW.