Objectives: To determine whether 12 initial weeks on a Very Low Calorie Diet (VLCD) included in a two-year support program is associated with better long term weight loss maintenance than a dietary and behavioural support program alone. Additionally, to identify characteristics associated with successful treatment or attrition, which can be used in selecting individuals likely to respond to VLCD-programs.
Design: Randomised clinical trial.
Setting: Two Swedish out-patient clinics.
Subjects: 113 obese men and women aged 37-58 y, body mass index (BMI) > 32.0 kg/m2, participating in the Swedish Obese Subjects-(SOS) study.
Interventions: One group received VLCD for 12 initial weeks plus regular dietary and behavioural support over two years while the other group received two years of the same supportive program only.
Main outcome measure: Weight loss after two years treatment.
Results: Both treatment groups maintained highly significant weight losses at two years but the initial VLCD-treatment appeared to have given no significant long term benefit compared to the supportive program. Examination of selected demographic, psychosocial and dietary characteristics showed that the VLCD-approach was more effective than the supportive strategy alone in men and possibly in individuals sharing household with only one person. High initial hunger-score was associated with attrition, irrespective of treatment.
Conclusion: A VLCD-program including long term dietary and behavioural support is a successful treatment for some severely obese subjects, especially men. Further research should be directed towards matching treatments to individuals in order to improve the high recidivism rates generally following weight loss attempts.