Which is more important? If you want to get big, eat; if you want to get strong, lift! It really is that simple. I'm always confounded listening to my female colleagues - each one of which is always wishing she were a few pounds (stones) lighter.
I've endured tales of everything from diet coke only(!) diets to some crap about a "raisin detox" (not sure what these mysterious - and undetectable - toxins are, nor what good is expected to come of eating 1Kg of raisins every day for a week.
And when I suggest weight training, I'm usually met with looks suggesting I've slept with their sister, mother and cousin, and uploaded the video evidence. Most women seem to think that coming into contact with a barbell or any serious weights will turn them into this: