You haven't established that cancer in meat eaters is largely caused by eating meat, whereas it is quite clear that overall cancer rate drastically increases in smokers.

In fact, while vegetarian diets do reduce the risk of cancer, the difference is by comparison modest - the overall risk of cancer in vegetarians is ~10% lower.

That isn't true. There are causal links between meat and cancer. You have: IGF1, saturated fat, sulphar-based animo acids like methionine, mycobacterial load, oxidative stress, purification in the intestine and more recently, that nuXX sugar found in protein.

Did you read my comment?

I didn't deny causal links between meat and cancer. I denied that the causal links between meat and cancer caused anything close to as much additional total cancer risk as smoking does. That's a viewpoint that is supported by any credible source you care to name.

Vegetarians still consume proteins from animals like casein and cholesterol from eggs. There have been a lot of studies connecting casein to cancer as well (when protein intake is over 7% from calories).

This is a perfect example of confusing correlation with causation.

The WHO report is very clear: red meat and processed meat cause an increase in risk of some cancer. And they're very clear that it's causal, not just correlation. And they're clear that the risk is increased by 15-20%. But that increase is on a very low risk.

"This is a perfect example of confusing correlation with causation." You are confusing two different fields of science. This isn't physics where an action causes a reaction. This is biology and the human body is a massive ecosystem. The 800 studies that "eventually" reached the WHO is the best way to determine a connection between two things. This is decades of research and maybe around 1million human subjects that were studied in total.