Good questions. An
energy deficit is ALWAYS going to lead to tissue loss. That said, sure, you could eat crap and as long as you were burning more
energy than you were consuming, you would experience
weight loss.
If you are going after
FAT LOSS though, a little more due diligence must be taken IMO.
There are certain baselines that I believe are necessary in order for proper
body recomposition (lose
fat, maintain muscle) to take place. In terms of dietary needs, these things include, but are not limited to, adequate protein consumption and EFA consumption. Beyond these two things, how you make up the remainder of your caloric intake is extremely individual and
goal dependent.
To answer your question, I have seen people eat the right things in order to maintain muscle and eat crap on top of that and they have developed great physiques. That said, I also like the saying, crap in, crap out. Eating crap certainly isn't optimal for health, longevity, performance, or whatever else you want to look at.
Weight gain and loss is dictated almost entirely by
energy balance. Fruit has
energy in it. So, if your maintenance level is 2000
calories, yet you eat 3000
calories of fruit each day, you will gain weight, assuming you are not burning off the surplus through activity.
Take home point. If all you care about is what the number says on the scale, and nothing else including
body composition, how you feel, health..... eat whatever the heck you want as long as you maintain an
energy deficit.
Do I recommend this? Certainly not.
