Here's a little question.

When it comes to bulking, people keep saying 'eat alot of clean food'

What would you consider to be 'clean' then?

Full cream milk?
Whole eggs?
butter?
whole cheese?

I mean, these foods are high-caloric and are natural products after all too.

Or would you define clean food as 'low glycemic, low fat, yahdahyahdah'?