Efficacy for those with type 2 diabetes in the United States
A 12-month randomized controlled trial in 563 adults with type 2 diabetes (72% female, 55 y, 104 kg, HbA1c 8.4%) found that those who received Weight Watchers (WW) meetings and digital tools plus telephone and email consultation with a certified diabetes educator lost significantly more weight than those in a standard care (SC) program, according to a 2016 study published in Obesity. Those participating in WW lost 4.0% and those in the standard care program lost 1.9% at 12 months.
Additionally, those in the WW group had significantly greater improvements in their HbA1c. Specifically, the WW group experienced a decrease of 0.32%, compared to the standard care group which showed an increase of 0.16%, at 12 months.
A 2017 article published in the Journal of Diabetes and Its Complications on the quality-of-life relevant psychosocial measure collected in the aforementioned 2016 Obesity study found that those with type 2 diabetes in the WW group had significantly greater improvements in diabetes distress and weight-related quality of life than those in a standard care program.