I have personal experience with overly ambitious dieting—relying solely on chicken breast and Americanos—and I remember feeling dizzy and losing focus. Having been through that struggle myself, I fully understand your perspective. In Traditional Korean Medicine (TKM), we prioritize the 'flow of Qi and Blood' and the 'condition of the digestive system' over simple calorie restriction. Relying on low-calorie drinks or fasting can easily lead to Spleen Deficiency (脾虛). When the function of the Spleen is weakened, nutrient absorption is impaired, which ironically drives the body to crave stronger sweets. Therefore, I recommend the following approach: First, check your digestive state—whether you frequently feel bloated or if your abdomen feels cold. This is because accumulated waste, known as Phlegm-Fluid (痰飮), may be stagnating in your body and slowing down your metabolism. Second, instead of focusing solely on reduction, we must employ Tonifying Methods (補法) appropriate for your constitution to build the energy necessary to maintain your basal metabolic rate. Additionally, clearing Blood Stasis (瘀血)—'bad blood' that obstructs circulation—will ensure that energy is delivered efficiently to every part of your body. Finally, gradually transition from low-calorie drinks to a diet that provides the actual nutrients your body requires. The essence of a successful diet is ensuring your body does not feel it is starving. Let's work together to determine your specific constitution and identify where your energy flow is blocked.