Objective: Weight-loss maintenance following very-low-calorie meal plans is poorly studied. This report describes weight-loss efficacy and predictors of weight-loss maintenance of a ketogenic, very-low-calorie meal plan (protein-sparing modified fast, PSMF) in people with obesity.
Methods: A total of 127 consecutive adults in the PSMF meal plan (27.2 ± 19.5 weeks) and 48 adults on a conventional, hypocaloric meal plan (23.6 ± 20.8 weeks) were retrospectively studied for percent weight change from baseline to end of intervention and at 6, 12, and 24 months postintervention. Baseline factors were analyzed for correlations with weight-loss maintenance.
Results: At end of intervention, weight loss from baseline was greater for the PSMF group compared to the conventional intervention group (-12.4% vs. -2.6%; P<.001) but was similar between groups by 12 months postintervention. PSMF subjects who attended follow-up visits to receive instruction on gradual and limited carbohydrate refeeding after ketosis saw significant weight loss at the end of PSMF compared to those who did not follow-up to receive instruction (-17.5% vs. -8.0%; P<.001) and maintained greater weight loss through 12 months post-PSMF (-9.8% vs. -1.5%; P<.001). Higher baseline body mass index correlated with less weight loss at 12 months post-PSMF (P = .035).
Conclusion: PSMF results in effective short-term weight loss of more than 5% from baseline weight. Follow-up for limited carbohydrate refeeding instruction is important for weight-loss maintenance up to 2 years after initial weight loss.
Abbreviations: BMI = body mass index; PSMF = protein-sparing modified fast.