I think the theme looks nice. The colors all go together well. The only two suggestions I have for aesthetics would be:
1) Some sort of border around the header. The header looks a little bit weird just kind of floating the the background color. I think either a slightly contrasting bgcolor or maybe a logo or background image near the top would help it stand out a bit.
2) Maybe see if there's a way you can have the top navigation more evenly spaced horizontally so there isn't that dead space in the top right.
But all in all, I think it looks really nice.
On a related note, I run a website called
Strokes Suck, which was founded by my father after he had a stroke, in order to raise awareness of that disease. As you probably know, diabetes greatly increases the risk of stroke. I was wondering if you would like to trade links so that we could get a little "cross-awareness" going on about the connection these two have. What do you think?