No, vitamins don't affect ketosis. However, eating fat does, so it might just be that your stix are changing colour after eating fatty meals. The stix are notorious for being inaccurate, so please don't worry too much about them. Just another reason to forget about the &^*% stix, and concentrate on eating right.

As I've said many times here before, losing weight is far more important than changing the colour of a little piece of plastic.

Cheers.

Rosebud