For what it's worth, the body does hit plateaus during weight loss for 2 reasons:
- Adaptation syndrome: Our bodies adapt to exercise and reduce the caloric burn by operation more efficiently for the same given physical effort, resulting in a plateau.
- Our bodies prefer to burn the least efficient storing dynamic tissues first to keep a reserve. Fat is a static tissue, requiring very little energy to maintain, hence the body will burn that last.
That's the reason we supplement protein, by the way, to offset dynamic tissue loss (Muscle), until the body resumes burning fat again in it's normal cycle of burn after we cross the new threshold beyond the adapted new setpoint for the switch between The Kreb Cycle (Citric acid cycle or Sugars cycle), and the anaerobic cycle (Protein/Fat metabolism), as well as the switch within the anaerobic cycle from protein to fat burn resultant from long term effort at 70% Max HR.
The source of my data is Hole's Human Anatomy and Physiology, 2003 edition as well as several Sports Nutrition Sites and information obtained in Lecture by my A&P Professor, Dr David McBride, MD, PhD, Naturopathic Medicine and Nutrition.
Edit: By the way, this is NOT a "Fat Acceptance" concept, it's a medical fact, confirmed by a lot of research in nutrition and body chemistry.