Changes of dietary patterns during participation in a web-based weight-reduction programme.

OBJECTIVE To examine the weight-loss success associated with distinct dietary patterns and to determine changes of these dietary patterns during participation in a web-based weight-reduction programme. DESIGN Factor analysis was used to identify the dietary patterns of twenty-two food groups that were administered in 14 d dietary protocols at baseline and after 3 months. Successful weight loss (≥5% of initial weight) and BMI were calculated. Logistic regression analyses were used to assess the rates of weight-loss success from each dietary pattern and changing or remaining in the initial dietary pattern. A generalised linear mixed model was used to estimate the effects of changing or staying in a dietary pattern on change in BMI. SUBJECTS Adults (n 1635) aged 18-81 years. SETTING Users of a web-based weight-reduction programme (2006-2012). RESULTS Participants who aligned to a healthful dietary pattern at baseline (OR=1·8; 95% CI 1·5, 2·3) and after 3 months (OR=1·5; 95% CI 1·2, 1·9) had a greater chance of successfully losing weight. After adjusting for age, sex, initial dietary pattern and BMI, participants who started with or changed to the healthful dietary pattern had a greater chance of being successful (OR=1·4; 95% CI 1·1, 1·7) and a higher BMI reduction of 0·30 (95% CI 0·2, 0·5) kg/m(2) compared with those who started with or changed to the energy-dense or high-carbohydrate dietary pattern. CONCLUSIONS A favourable healthful dietary pattern at the beginning and after 3 months was positively associated with anthropometry. However, successful weight loss was feasible in each dietary pattern.