There is no set definition for "clean" when it comes to food. It is a subjective word and every one has a different opinion/bias towards it. If you want to read and learn more in depth on it, check out this article:
The basics to losing/maintaining/gaining weight is calories in vs calories out. There are some other variables that come into play, but this is a nice place to begin at and adjust accordingly. So if you want to lose weight, you need your body to use up more calories than you put in (caloric deficit). This can be done by eating less or doing more work. I think most people would recommend to do more work since you don't want to end up like one of those people who eats only 800 calories a day.
"Strength is the product of struggle, you must do what others don't to achieve what others won't."
Squat: 463 Bench: 275 Deadlift: 529 Total: 1262
"Technique is always the first place to begin when striving to improve at a specific skill."
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