I really like the theming of the veggie vs. junk food, but as others have said, it was extremely difficult to see the many of the bullets. Beyond that, I also think it would be nice to stylize the bullets to also be food themed, rather than just being simple circles. Maybe the ice cream enemy shoot's little scoops or cones? :)
The game itself is fairly straightforward. I enjoyed the power-ups and upgrade system between the waves, and the audio is satisfying. However, I did find it a bit odd that the veggie makes a grunting sound when it's hit.
Overall nice job!