Does it matter what I eat tow days BEFORE a colonic?

I going to have a colonic in the next two days. I was told not to eat any dairy products or fried foods, sugar, junk foods, in order to avoid gas, which I don't understand. Actually they told me not to do this for a week, however I made the appointment 3 days ago. They said it was fine that I was eating the same way I used to, but make sure you stop two days before your appointment. So I'm trying to prepare and eat healthy, but I bought salad dressing and veggie chips that contain milk. What should I do? I then realize that the colon therapist did not tell me to avoid spicy foods, which to me causes the most gas out of everything. Does it really matter what I eat until I get my colonics?