Multicenter Evaluation of Health Benefits and Weight Loss On the Medifast Weight Management Program Crowell, M.D. and Cheskin, I. J. The Johns Hopkins University School of Medicine ABSTRACT Despite the popularity of protein-sparing modified fasts, relatively few efficacy studies have been published. The purpose of the current investigation was to retrospectively evaluate the efficacy of a medically-supervised, protein-supplemented modified fasting program (Medifast) for weight reduction and to evaluate the impact of weight reduction on coexisting health problems. Method: Twenty patient charts were randomly selected from each of 20 randomly selected Medifast clinics nationwide. Only patients completing the program in the past two years were sampled. Forty-six percent (185 patients) completed at least 16 weeks on the program (M=23.65-0.61 weeks). Individuals sampled were primarily female (83%) and Caucasian (90%). The average age for males and females was not different (43.60-10. 3 and 42.73-10.7 years, respectively). Body mass index at entry for males was 43.20-10.86 kg/m.2 and for females was 36.63-7.61 kg/m2. Results: Males lost an average of 67.41-54.6 lbs and females lost an average of 47.5-17.4 lbs during fasting. Ninety-one percent of males and 72% of females lost more than 40 lbs on the program. As previously reported, males lost weight at a faster rate than females. However, males and females showed decreases in BMI of similar rates. Total weight loss showed a significant positive correlation with beginning weight. Significant reductions were seen in systolic and diastolic blood. pressure, total cholesterol and triglycerides. Blood pressures were normalized in 90% of hypertensive patients. Only minor, transient side effects were seen during the modified fast. The most common complaints were headaches, fatigue, lightheadedness and cold intolerance. These symptoms were most common during the first 8 weeks of the diet. Gallbladder symptoms were reported in only 1% of the patients and no patients underwent gallbladder surgery during the program. Conclusions: Medically-supervised, protein-sparing modified fasts offer a safe, effective means of weight reduction and are accompanied by significant improvements in coexisting health problems.