Not sure about the calcium, although a year ago doctors found that I was really low in vit D and couldn't figure out why (docs only suspecting CF very recently). Seeing that calcium and vit D are related I should prob get it checked again. At the time the only thing that they could come up with is that maybe I was inside too much - people get alot of vit D from sunlight (which is balony because I'm outside constantly). They put me on 50,000UI of vit d for several months.