Yo-yoing is not a matter of willpower, but a result of 'homeostasis'—the body's innate tendency to maintain its internal stability. To prevent weight regain, you must identify your specific physiological state based on Traditional Korean Medicine (TKM) principles: 1. If you struggle with appetite control and experience 'false hunger,' you may be in a state of Spleen Deficiency (Bi-heo, 脾虛). When the Spleen's function is weakened, nutrient absorption and transport are impaired, leading the body to signal a constant need for food despite adequate intake. In this case, restoring digestive function is the priority to prevent the yo-yo effect. 2. If you experience bloating and slow weight loss despite eating less, you may have accumulated Phlegm-Fluid (Dameum, 痰飮) or Blood Stasis (Eohyeol, 瘀血). When metabolic waste stagnates, the circulation of Qi and Blood is hindered, lowering metabolic efficiency. Rather than fasting, it is crucial to use prescriptions that promote circulation to 'clear the paths' within the body. Ultimately, preventing the yo-yo effect requires healthily resetting the weight your body 'remembers.' Prioritize improving your metabolic capacity over aggressive weight loss. I suggest an accurate diagnosis to determine whether you are suffering from Spleen Deficiency or stagnation of Phlegm-Fluid to begin a customized management plan.