Q. Doctor, what exactly is a weight loss plateau, and why does it happen?

Many people experience a frustrating moment where weight loss suddenly halts despite their best efforts. This is actually driven by the body's survival instinct; the human body prioritizes homeostasis (stability) over change. When caloric intake drops sharply, the brain triggers an 'emergency mode,' reducing energy expenditure to preserve survival. In Western medicine, this is known as the resistance of the 'set-point.' From a TKM perspective, the causes are more specific. Rapid dieting often leads to 'Spleen Deficiency' (Bi-Heo, 脾虛), meaning the functional capacity of the Spleen to transform and transport nutrients is impaired, causing metabolic efficiency to plummet. Furthermore, if the pathways of circulation are blocked by 'Phlegm-Fluid' (Dam-Eum, 痰飮—metabolic waste) and 'Blood Stasis' (Eo-Hyeol, 瘀血—stagnant blood), waste products cannot be efficiently expelled from the body regardless of how little you eat. Essentially, your metabolic 'engine' is slowing down while 'sludge' continues to build up in the system. Ultimately, a plateau is not a failure of willpower, but a signal that your metabolic switch needs to be reset. The most effective approach is to accurately diagnose whether your condition is rooted in Spleen Deficiency or an accumulation of Phlegm-Fluid and apply a tailored herbal prescription to restore balance.