and in fact I was eating whatever and drinking wine and margaritas during my last cycle since I was moving on to DE. I wanted to indulge since I was free of the OE cycling.
But obviously my eating and drinking didn't impact my ability to sprout a single follie that cycle that eventually led to my healthy DD being born this past August.
I did cut out caffeine a couple years back and that was primarily because I wanted to "prep" for the day I'd be PG and would need to cut it out anyway.
If you're fine with making the dietary changes, then go for it. It won't hurt and could improve your overall health. Just be sure to take a Vitamin D and Calcium supplement if you're cutting out dairy altogether (and assuming it was a large part of your diet to begin with).