These ‘X % of cancers are due to lifestyle’ statements are an extrapolation from observational data we know is confounded and are an overestimate for sure. What they mean by ‘lifestyle’ isn’t even consistently defined, and thus has no predictive let alone explanatory power. Just look at the data from animals, they get cancer all the time and they aren’t eating cheerios and binge drinking. Cancer does effect smaller animals just as much [1].

[1] https://www.nature.com/articles/s41586-021-04224-5

One other major factor people also overlook is genetics - not that you can do anything about it, but if you have cases of cancer in your family, you should probably be extra careful. Plus the obvious things like fair-skinned people needing to be more careful about skin cancer etc.

Pretty much everyone has some cancer in their family. Cancer is really common.

You won't always know there was cancer, though: How often do you hear about Grandpa's prostate or that mole your cousin had removed?

That’s always shared among the family. Don’t know where you are from.

No, it most definitely isn't. I'm originally from the US, by the way. The midwest, if that helps. Some families will talk about it, others don't, and a lot will pass on talking about it if it was 'no big deal'. So the weird mole? Yeah, you probably didn't hear. You especially didn't hear if it was your cousin. Not everyone will talk about their prostate, especially folks more embarrassed about bodily functions or anuses. A lot of prostate cancer doesn't require treatment, after all, and no reason to talk about it. If your great grandmother had cancer, you probably don't know, especially if she died from a heart attack or stroke. Doubly so if your parents and grandparents are still alive and have not had cancer.

And yes, I've met all sorts of folks like this. I worked in a pharmacy for years.

You just assume everyone will talk about such things.

Ok I see. I’m from Italy and I know what medications my grandfather takes, that my grandma had cryosurgery for a malignant mole, and when my father goes to the proctologist.

Also: families usually go to the same doctor so even if you don’t personally know something, your doctor probably will.

Ah, yeah, definite difference. Even when I was a child, we didn't go to the same doctor as my parents. My parents went to doctors that specialized in adults and wouldn't take patients under 18 - and it has been some time since I lived in the same town as my parents. Heck, it has been nearly a decade since I lived in the same country.

As far as I can tell, the US and Norway are similar - but heck, I'm an immigrant and haven't actually looked into this.