I have struggled with this same issue, i spent a long time looking at the right stuff to eat. Small and often is the trick, however i found that i'd get too tempted whilst on, and instead of a protein shake i'd reach for some solid food (usually unealthy)
Tapering carbs towards the end of the day seems to help, i also hear somewhere that potato can cause insulin spikes.
tuna, skinless chicken breast (i wouldnt even bother pretending the kfc type chicken is beneficial) and other lean meats, veg that is low in calories such as green beans, carrots, sweetcorn. you can usually buy microwavable steam bags of veg, i found these very usefull.
portion size and whats in it is the most important imo. I was speaking to an amazingly ripped guy the other week who was prepping for a natural contest and he said that he doesnt count calories but just looks at portion size and makes sure EVERYTHING he eats is natural, so no processed anything.
when you look into it, at the supermarket, you have to go out of your way to actively seek foods that have not had millions of e numbers added, or any meat that hasnt been injected with water to make it look nice.
hope that helped,
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