Examination of whether early weight loss predicts 1-year weight loss among those enrolled in an Internet-based weight loss program

One-month weight loss (WL) predicts post-treatment WL in face-to-face interventions; however whether this holds true within Internet programs is unknown. This study examined whether 4-week WL predicts WL following a 12-week Internet program and at 6 and 12 months follow-up. 181 participants (BMI=33.4±5.5kg/m(2); 83.1% female) received a 12-week behaviorally-based Internet WL program consisting of weekly video lessons. Participants were given a daily WL, calorie, and physical activity goal and asked to enter these data on the study website weekly. Personalized feedback was provided. Using 4-week WL, individuals were categorized as ‘early non-responders’ (<2.0% WL) or ‘early responders’ (≥2.0% WL). Early non-responders had significantly lower WL than early responders at 3 (-1.3±3.8% vs. -6.3±4.3%), 6 (-1.7±5.1% vs. -5.8±5.2%), and 12 months (-0.05±6.8% vs. -2.7±6.3%, p's<0.05). The odds of achieving a ≥5% WL were 8.5 (95% CI:3.3–22.1), 3.4 (95% CI:1.4-8.3), and 2.6 (95% CI:0.93-7.4) times lower in early non-responders, compared to early responders at 3, 6, and 12 months respectively. Compared to early responders, early non-responders viewed fewer video lessons and self-monitored less often across the 12-week intervention (p's<0.05). This study provides initial evidence that a 4-week WL of <2.0% places an individual at an increased risk of failing to achieve clinically significant WL following an Internet program.