And then add a tax to either the more refined flours (which is likely to make sweet baked goods go up in price as well) or simply tax the more unhealthy white bread and buns so they aren't nearly as affordable.

Edit: I'll mention that some salt is actually good for bread making, as it balances out the yeast. I'm not sure if this is such a problem on an industrial scale since they can control variables much better than the home cook. In addition, it tastes weird without salt. but it doesn't take all that much to satisfy the physical and taste requirements.

Furthermore, I'll advocate for a bit of fat in the bread, though it should come from healthy sources. This helps bread not go stale so quickly, and I'm actually more concerned about unnecessary preservatives.

Finally, an afterthought: We should make sure to make the healthy bread convenient and available, even in a food desert.