Judging by the physical structure of heterocyclic amines, I would hypothesize that the carcinogenic properties result from their ability to intercalate with DNA (that is, they stick themselves between the base-pairs). This causes deformation of the DNA, which affects the ability of DNA replication and repair enzymes to properly bind to and act on DNA.
Since some essential nutrients are also heterocyclic amines, I would also hypothesize that the carcinogenic heterocyclic amines are resistant to enzyme action that would normally shunt them into various metabolic pathways for further processing.
I also happen to be a biochemist, PhD type.
Would stress levels mitigate this?
Say in sedentary adults vs “actively in training” adults.
In their sampling, the bottom age of the survey was apparently 50 years of age. Changes in insulin sensitivity, IGF-1, GDF-8, IGFBP-3, etc ... should be entirely different for those adults who are active vs those who enjoy their late-middle years by docile activities.
Not a PhD here... Just someone with a strong interest, pun intended, in maintaining my weightlifting and activity levels for as long as I can. The benefits have, so far, outweighed any potential risks. If I need to moderate my diet here in a few more years to avoid cancer... I’d prefer to know the Why as well as the How...