I just received a call from my doctor saying that I needed to start taking 5,000 units of D3 for a month and then to taper down to 1,000 afterward. So I am curious if anyone else has been diagnosed with this problem?

I have read online a slew of things it can cause. Most of them I haven't noticed aside from being a bit more depressed than what is normal for me at this time of year. It also says it can make it difficult to maintain and build muscle mass, which I think may be a problem for me too. I am currently preparing for a lengthy race this summer and the weight workouts have been absolutely wiping me out. I don't remember feel so wiped out like this before? I REALLY hope the supplements help.