It’s been said for years that bread made from flour coming from so-called “processed” grain (endosperm only) is utterly unhealthy. Just dogged denial catching up to reality.
White flour is about the worst thing you could eat.
How about white rice? The Japanese eat it by the truckload and their lung cancer rate (and cancer rate in general) is much lower than the rate here in America. And this despite the fact that they SMOKE more too.
There was almost never white bread or rice on the table when I was a kid-we lived in the country, so whole grain was easy to find. I still don’t eat processed flour or rice-or any other processed food-I still live in BFE and there is a small mill not too far away that sells whole grain flour-and brown rice is available everywhere.
That said, I doubt bagels would do you in unless you ate enough of them to be morbidly obese...