Marnie Walston

The purpose of this pilot study was to assess the acceptability to adolescents (11–18 years old) and their parents using a revised protein-sparing modified fast (rPSMF) for 12 months as an intervention for severe obesity in a tertiary pediatric weight management clinic (PWMC). To assess acceptability (satisfaction, confidence) with the rPSMF protocol, surveys were completed by adolescents and parents at baseline, 1, 3, 6, and 12 months, with adolescent height and weight measured. Analyses were conducted to assess differences in satisfaction and confidence based on adolescent response (weight loss) and adherence to the rPSMF. Adolescents’ adherence with the rPSMF was close to 50% in the first 3 months, but dropped to 14.7% at 6 months. Adolescents were most confident with choosing low carbohydrate foods at baseline. Over 12 months, adolescents and parents reported weight loss as “the most liked” part of the rPSMF. Adolescents who were adherent were more satisfied with their weight loss than their non-adherent peers. Parents and adolescents reported lack of food variety and difficulty following the protocol as challenges with the rPSMF. Adolescents and their parents were able to follow the rPSMF protocol, with weight loss, but with decreased adherence over time.

Treatment options are limited for children and adolescents with severe obesity. One alternative treatment is the protein-sparing modified fast (PSMF), a low-carbohydrate, high-protein diet that can result in substantial weight loss. The aim of the study is to evaluate the adherence and efficacy of a revised PSMF (rPSMF) for severe obesity in a pediatric tertiary care weight-management program. The rPSMF with 1200–1800 calories, 40–60 g of carbohydrate/day and 1.2–1.5 g protein/kg of ideal bodyweight was implemented over 12 months. Twenty-one participants enrolled in the study. Mean age 16.2 ± 1.4 years, females (76.2%) and mean weight at baseline was 119 ± 19.9 kg. Regardless of adherence to the rPSMF, the mean weight change at 1 month was −3.7 ± 3.5 kg, (range −13.5 kg to 0.9 kg); at 3 months was −5.5 ± 5.1 kg, (range −19.3 kg to 1.8 kg) and at 6 months was −4.7 ± 6.6 kg, (range −18.3 kg to 8.6 kg). At 12 months, the mean weight change was −1.3 ± 10.6 kg (range −17.7 kg to 14.8 kg). Parent and child-reported physical and psychosocial quality of life (HRQOL) improved. Despite limited adherence, the rPSMF diet resulted in clinically significant weight loss and improved HRQOL for children and adolescents with severe obesity.