Purpose: To study the effect of the National Diabetes Prevention Program (NDPP) on weight loss in Latinos.

Design: No-control, cohort study comparing Latino and non-Hispanic white (NHW) participants.

Setting: A health-care system.

Participants: Five hundred sixty-seven Latino and 175 NHW patients who enrolled in the NDPP. A total of 45.2% of Latinos selected the Spanish-language NDPP.

Intervention: The NDPP is a nationwide translation of a clinical trial and seeks to prevent diabetes through weight loss in a yearlong group program.

Measures: Independent variables included ethnicity, class language, and number of sessions attended. Main outcomes were initial attendance, number of sessions attended, and weight loss.

Analysis: Multivariate logistic regression and analysis of covariance were used to determine differences in NDPP outcomes by ethnicity, language, and number of sessions attended.

Results: Mean attendance was 8.60 of 22 sessions. Each session was associated with 0.30% (±0.02; P < .001) body weight loss. Latinos were half as likely to attend as NHWs, odds ratio 0.52 ( P < .001). Latino attendees came to 2.67 ± 0.63 ( P < .001) fewer sessions than NHWs. There were no weight loss differences by ethnicity after controlling for attendance. Outcomes did not differ among Latinos in the English- and Spanish-language NDPP.

Conclusion: Latinos appeared to benefit less from the NDPP compared to NHWs, likely due to lower attendance rates. Further efforts are needed to support their participation.