I like the execution on this, but I have to say that I'm not getting a sundial.
I get a shark. It's just my first impression and when I saw that it was supposed to be a sundial I understood that you were emphasizing the constant nature of the disease and (I assume) the services that the company offers, but I still read the 'ripples' as water and the actual sundial itself as a shark's fin.
I think that the 'ripples' I mentioned above are the issue, largely. I also think that the shadow isn't strong enough on dark backgrounds to emphasize a relation to 'sundial' over 'shark' (and I tend to think that your association with time rather than with the medical side of things is slightly too abstract to carry the mark through to comprehension)
I hope you don't take this the wrong way - it's a well done mark, but I think some things are inconsistent with the direction that you're taking this.
Despite you wanting to give diabetes something "everyday", I'm missing the medical element in this. And I know what I'm talking about, I've been diabetic since I was six And despite living a fairly normal life, it's always pretty much "there". I like your idea, but it's missing something...I do like the way you built the logo though, it has depth and it's sleek. I especially like the font you chose for it, well done!