two products sharing a given ingredient does not inherently mean that consuming it is unhealthy, its just a catch tag line for the papers.
Its all good, however, the sad part is that legitimate business (subway and others associated with the additive) may take a hit from this. Not to mention, the credibility of food additives in general is put on the chopping block without legitimate grounds. This happened to BPA and vaccines. As someone really into science this sort of reporting pisses me right off.
them chemical additive in question is azodicarbonamide. The fad regulated max allowed in foods is 45 ppm, which is exponentially less than a quantity that would even theoretically (although it was tested) case significant affects.
If your using college internet, check this out
http://www.ncbi.nlm.nih.gov/pubmed/16192074