I'm going to second (or third...)the "don't get worked up about the color of your ketostix!" post. If it gets very dark purple, that likely means you are dehydrated. There are the same amount of ketones in your urine, it's just in a smaller volume, so the test will pick up a greater percentage. For an analogy: Think of a teaspoon of salt in a cup vs. a gallon of water.... It's still a teaspoon, but the perception of saltiness will differ. Hope that helps!