Has there been an increase in red meat consumption? That seems to be an unlikely culprit.

I think there has not or not much. However, we seem to consume the meat differently like processing it heavily, cooking it at very high temperature. These actually produces lots of carcinogens that add up over time. Sugary food can cause lots of body inflammation which can fasten the process.

coinkydental that they mostly come in plastic packaging, too.

That could be as well, but we haven't had lots of evidence yet(maybe due to the blocking of plastic industry).

By the time we totally understand the plastic impact on our health, it may be too late.

i don't know if i agree that it possibly will be too late—but i sincerely doubt i'll be around long enough to find out one way or the other. i think that's another inherent part of the problem.