&gt; Conversely, you can gain body fat while losing lean body mass with a calorie deficit.<p>Do you have any sources for this? I&#x27;m curious because it matches my experience the handful of times I&#x27;ve attempted even fairly harsh caloric restriction. A month or two in and my weight drops such a small fraction of what all &quot;weight loss&quot; calculators suggest it should (like, 1&#x2F;20) that I doubt the &quot;calories in, calories out, it&#x27;s so simple bro!&quot; crowd would believe me.<p>Meanwhile, anaerobic exercise cuts fat and builds muscle on me like crazy. Way, way more effective. Too bad since I find it way easier to cut calories (time commitment of zero, if not negative).