Could it be due to diet? Soda, fast food, that kind of thing?
Wonder how many of them are Vegans?
most likely gay men skewing the numbers
Could also be other things, like mixing of populations, and increased sexual partners. There are lots of viruses humans carry which don’t really produce symptoms, but can produce cancers at some point. And in the GI tract a lot of viruses, even plant viruses like PPMV can infect other types of cells, replicating somewhat in bacteria and yeasts in the gut, even epithelial cells lining the lumen of the intestinal and colon tissue. And there are even some bacterial associated with higher Colon cancer risk.
You take all the populations all over the globe, mix them together, get them all seeping with each other before adulthood, you will get a lot of weird things begin killing people oddly until it culls out all the vulnerabilities and the populations all adapt to each other’s bugs.