Karen Miller-Kovach, co-chief scientific officer at Weight Watchers International Inc. and a co-author of the study, said those in the Weight Watchers group were provided with three access routes -- group meetings, mobile applications and online tools. Further analysis found those who used all three access routes together lost the most weight, the study said.
Of the 292 overweight and obese adults who participated in the six-month trial, those assigned to the Weight Watchers group were eight times more likely to achieve at least a 5 percent weight loss than those assigned to lose weight on their own.
Among the 147 participants assigned to the Weight Watchers group, those using all three access routes to a high degree -- defined as more than 50 percent of the weekly meetings and using the mobile applications and/or online tools two or more times a week -- had the greatest weight loss at 19 pounds.
Those using two access routes to a high degree lost 9.5 pounds and those using one lost 9.3 pounds.
Meeting attendance was the strongest predictor of weight loss compared to usage of the other access routes, Miller-Kovach said.
"This clinical trial demonstrates that when Weight Watchers meetings, mobile applications and online tools are used in combination, the greatest weight loss is achieved," lead investigator Craig Johnston, an assistant professor at Baylor College of Medicine in Houston, said in a statement.
The findings were published in the American Journal of Medicine.