I don't think it's beneficial to look at bread so reductively. Effects of bread on weight (or health) depend on the type of bread, quantity, and the person having it.
For example I eat homemade sourdough bread with lentils and greens. And I'm very lean. Eddie hall also eats some sourdough btw.
For thousands of years, we ate bread and didn't get fat. It's been a fundamental source of nutrition so much so that it has become a synonym for food.