I think Helen was talking about the ratio of acetylcholine and gaba regarding POIS and the activity of the thyroid and adrenals.
Can u explain?
I know that nicotine seems to increase my metabolism and it increases acetylcholine from what I know, so that may help answer your first question.... or could be some other interaction.
I would also exclude niacin, as it also increase Prolactin. Maybe afterwards it rebounce with increasing ACTH, but there is group of people who take huge amounts of niacin to increase their height, by raising growth hormone.Yeah, nicotine + niacin + b1 + manganese all increase acetylcholine. Acetylcholine raises ACTH and Cortisol.