From a modern medical perspective, caffeine stimulates the release of adrenaline, which helps mobilize fatty acids stored within fat cells, placing the body in a state where it can more readily utilize energy. In Traditional Korean Medicine (TKM), this process is similar to forcibly boosting one's 'Qi' (vital energy). However, if a person suffers from 'Dam-eum' (phlegm-fluid retention, where metabolic waste accumulates) or 'Bi-heo' (Spleen deficiency, leading to poor energy production in the digestive system), relying solely on caffeine can be counterproductive. It is like revving an engine at high speed when there is actually no fuel to burn. This often leads to a sudden drop in vitality and an increase in 'false hunger,' which frequently culminates in binge eating. Therefore, I do not recommend coffee indiscriminately. It is crucial to first assess the presence of 'Eo-hyeol' (blood stasis, where stagnant blood impedes circulation) and ensure that your digestive function is strong enough to handle the stimulation. Checking the current state of your body's 'engine' and finding a complementary approach tailored to your constitution is the starting point for a diet that prevents the yo-yo effect. If you have concerns about your specific constitution, I encourage you to visit the clinic for a personalized consultation.