YES on all counts.

My hormone problem manifests with Cortisol Resistance; my body is making lots of cortisol but it's not getting into my cells. Chronic inflammation from chronic stress. So niacin (with the B & C chaser) actually seems to let the cells heal from whatever has caused their dysfunction. Dr. Saul studied under Dr. Abram Hoffer, who used it with great success on POWs from WWII in Canada.

I stumbled into the link between chronic inflammation and sleep problems when I was using white willow bark for a fever, and discovered it helped me sleep better. But niacin is much better for long term use.