To me "eating clean" means eating mostly vegetables by volume and mostly fat and protein by weight. For instance typical ketogenic/paleo diet. Eating "dirty" is

To me "eating clean" means eating mostly vegetables by volume and mostly fat and protein by weight. For instance typical ketogenic/paleo diet. Eating "dirty" is theoretically doable. If one prototypical example of eating "dirty" is having a standard supermarket cake slice or mound of cereal and milk to fulfill daily caloric needs, then it is actually harder to maintain a "dirty" diet. Satiety becomes an unattainable goal. We simply cannot handle the insulin spikes well. We get hungry and cravings are more intense with such a diet. It is essentially impractical. It may also explain why there are so many obese in the world. "Eating clean" can be used as a marketing term to get people to fork over huge bucks for an oversold concept. But fundamentally, "eating clean" the way I define it is very cheap, tasty, and pragmatic. Especially for losing weight and maintaining a low weight.