They discovered that we have these molecular pathways that are responsive to light and allow the body to synchronize to the comings and goings of the sun. When that is working at its most effective, and all the cells are working as a team, overall health is much better. I think most people don’t understand the importance of light and how we consume it. Artificial light is completely at odds with our biology.
The latter portion of this plan is meant to tidy up some of the loose ends, including conditions that can undermine sleep. If the early changes haven't proven to be effective or relevant, it may be because other issues are at play. Ultimately, if your efforts aren't rewarded in the end, it may be useful to speak with a sleep doctor who can provide you the personal assistance you need to overcome any remaining problems. This advice is generally good for all, but carefully crafting it to attend to your individual needs may make it invaluable.