Don't want to take the thread off topic, but it's interesting what you say about Vitamin D. Mine was (or still is, i don't know) quite low, but i didn't know about it for a long time. It's no wonder, i don't stay in the direct sunlight much, because i don't feel good if i do that. It's rather surprising doctors don't check your Vitamin D if they know you stay indoors a lot. For whatever reason i felt a bit more energy with the low Vitamin D, i think. But i also always had that feeling like i was using up my resources in some way. Like i need less sleep and have more energy, but i'm using up my substance. Maybe i was feeling this in some way. Either way, when i read what it says on the lab report about low Vitamin D, i don't think i would take the risk to live with a low level. It can lead to all sorts of bad things and so i, personally, would not experiment with that. But i don't know Dr. Cheney's theory and also i have no medical education.