>You can't deny the fact certain foods, like processed meat, surely have a causal relationship to cancer, probably also heart disease and diabetes
Based on what? Your gut feeling?
>getting cancer from tofu
There aren't case studies of people getting cancer from anything. There are studies of large population behavioral patterns and comparisons of cancer rates between patterns. So to check the tofu thing, you need people that consistently eat tofu compared to people that behave the same in other regards except for the tofu. That's very difficult because someone who eats tofu is generally going to have a significantly different diet from someone who doesn't.
Based on what? Your gut feeling?
>getting cancer from tofu
There aren't case studies of people getting cancer from anything. There are studies of large population behavioral patterns and comparisons of cancer rates between patterns. So to check the tofu thing, you need people that consistently eat tofu compared to people that behave the same in other regards except for the tofu. That's very difficult because someone who eats tofu is generally going to have a significantly different diet from someone who doesn't.