"Could", eh? Yeah, science doesn't get more definitive than that.
Bacon rasher? Is that where you you put a few slices in your underwear? Asking for a friend.
That is normal scientific language. We use those words because no scientist ever wants to be proven wrong, and we are dealing in areas that are so new that we don't really know all the facts. Science is a process of discovery, and it is always possible that more research will show the initial conclusions to be incorrect.
As for the study in question, I have not read it, but I suspect that it is one of those observational studies in which the input data is highly questionable and heavy statistical calculations were applied to come up with a correlation that merits further study. Very often, the authors of such studies take the correlation and run with it as if it is data derived from controlled testing, when it is not. It is absolutely the worst kind of study for actually gaining new knowledge.
For the record, I have no idea what a bacon "rasher" is. Is it bacon that causes hives?