Context: Weight loss programs on the Internet appear promising for short-term weight loss but have not been studied for weight loss in individuals at risk of type 2 diabetes; thus, the longer-term efficacy is unknown.
Objective: To compare the effects of an Internet weight loss program alone vs with the addition of behavioral counseling via e-mail provided for 1 year to individuals at risk of type 2 diabetes.
Design, setting, and participants: A single-center randomized controlled trial conducted from September 2001 to September 2002 in Providence, RI, of 92 overweight adults whose mean (SD) age was 48.5 (9.4) years and body mass index, 33.1 (3.8).
Interventions: Participants were randomized to a basic Internet (n = 46) or to an Internet plus behavioral e-counseling program (n = 46). Both groups received 1 face-to-face counseling session and the same core Internet programs and were instructed to submit weekly weights. Participants in e-counseling submitted calorie and exercise information and received weekly e-mail behavioral counseling and feedback from a counselor.
Main outcome measures: Measured weight and waist circumference at 0 and 12 months.
Results: Intent-to-treat analyses showed the behavioral e-counseling group lost more mean (SD) weight at 12 months than the basic Internet group (-4.4 [6.2] vs -2.0 [5.7] kg; P =.04), and had greater decreases in percentage of initial body weight (4.8% vs 2.2%; P =.03), body mass index (-1.6 [2.2] vs -0.8 [2.1]; P =.03), and waist circumference (-7.2 [7.5] vs -4.4 [5.7] cm; P =.05).
Conclusion: Adding e-mail counseling to a basic Internet weight loss intervention program significantly improved weight loss in adults at risk of diabetes.