My dad has been having some medical issues recently, which has been terrifying (total daddy's girl here), but they have been super aggressive about figuring it out. They just found out that his body doesn't process vitamin B6, which can cause permanent nerve damage at toxic levels. His levels were unbelievably high--they think they can get the levels down, but they're afraid that the nerve damage may be permanent. It's been a nervous few weeks. To top it off, this, like his Vitamin D deficiency, is probably genetic, so I have to go to my GP and ask for yet another off-the-wall blood test (my D levels did come back low, so at least I know to keep an eye on it now).
Really sorry to hear about your Dad and I hope he recovers quickly. I just wanted to say, though, that the Vit D deficiency didn't surprise me for you (or him). Frankly, IMHO, that should be a standard test for everyone in the UK. The current research suggests that women in particular are not getting nearly enough Vit D (same for older people). Here in the US, doctors seem to be picking up on this and I know many women taking what would once have been considered large amounts of it via supplements. Between people using sunscreen more often, not drinking much milk, and you not being able to get D in adequate amounts via food, the deficiency is reaching epidemic proportions. Plus, emerging rearch suggests that getting this vitamin is important in terms of preventing or alleviating some medical conditions and symptoms.
Why do I know all this? Because I was diagnosed with a shockingly low Vit D deficiency here in the US a couple months after moving back from the UK. Pregnancy had exacerbated it, but the lack of fortified milk and sun in the UK did not help. Some studies suggest the further north you live, the more likely you are to have low levels. There are also studies that are beginning to link up the increased rate in things like MS to living further north and lacking D.
Vit D deficiency is my pet topic (in case you haven't now noticed

). I think I posted about it evern more under Healthcare last year. So if your doc isn't being supportive of you, I can point you to a load of articles from reputable journals that discuss a lot of this. The recommended dose for D that I hear now is 800 to 1200 IU though there is debate about it - and the UK, if I recall correctly, only recommends 200!
OK, off my soapbox!
BTW, Vit D deficiency HURTS! It's what is called rickets in children!