Adherence

Structured commercial weight loss programs produce significantly greater weight loss and BMI reduction than self-help methods over a 2-year period, though both groups experience significant weight regain after the first year.

If you are trying to lose weight, joining a structured program like Weight Watchers is more effective than trying to do it alone with self-help resources. You will lose more weight and keep it off better for at least two years. However, expect some weight regain after the first year regardless of the method, so consistency is key.