Dietary intake in the Diabetes Prevention Program cohort: baseline and 1-year post-randomization

Purpose To describe usual dietary intake assessment at baseline and 1-year post-randomization in the ethnically diverse Diabetes Prevention Program cohort. Methods Participants were randomized to Lifestyle Modification, Metformin, or Placebo. Usual diet was assessed by a modified, previously validated food frequency interview. Results Complete data were available for 2934 subjects (90.7% of those randomized). Baseline median estimated energy intake was 7676 kJ/d (1828 kcal/d) and 8585 kJ/d (2044 kcal/d) for women and men, respectively. The median percent of energy from fat ranged from 30.6% for Asian American men to 37.5% for American Indian men and women. After 1 year among the Lifestyle group, the median change in total energy and percent energy from fat was −1897 kJ/d (−452 kcal/d) and −6.6%, respectively. For the Metformin and Placebo groups, change in median total energy was −1235 kJ/d (−294 kcal/d) and −1051 kJ/d (−250 kcal/d), respectively, and change in median percent energy from fat was −0.8% and −0.8%, respectively (p < 0.001 for differences between groups, adjusted for gender and ethnicity). Conclusions One-year post-randomization, significant differences in dietary intake were observed in the Lifestyle compared with the Metformin or Placebo group, and these were consistent with the general intent of the DPP lifestyle modification intervention.