Eating every few hours helps keep your metabolism elevated, which result in burning a greater number of calories at rest, in addition to keeping adequate nutrients flowing to your muscles.
Yes, your body will adapt to the caloric defecit and weight loss will slow down or ever stop, and just like training you need to do things to 'shock' your system into burning fat again. This can be using dietary techniques like carb cycling, CKD, or even clean bulking for a week or two. (or a combination off all those over time, ideally)
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