I've heard a few explanations, including that one, but haven't yet seen solid support for it. My oncologist suggested it may be related to changes in diet as a

I've heard a few explanations, including that one, but haven't yet seen solid support for it. My oncologist suggested it may be related to changes in diet as a result of the shift toward processed foods. I definitely was a part of that experiment, with lots of canned food and frozen meals when I was young.