The purpose of this study was to investigate the effect of the Stoplight Diet on blood glucose and HbAlc levels in overweight and obese non-diabetics. Additionally, the mode of intervention (ASPIRE phone-only, ASPIRE on-site+phone follow-up, and usual care MOVE!) and its effect on blood glucose and HbAlc levels was investigated. Specifically, this study examined the change in blood glucose and HbAlc levels (baseline to 3 months) in overweight and obese non-diabetic Veterans Health Administration (VHA) veterans participating in ASPIRE-VA in relation to: (a) percent change in the consumption of red foods in the Stoplight Diet, and (b) mode of intervention (ASPIRE phone-only, ASPIRE on-site+phone follow-up, and usual care MOVE!). Results showed that there was a significant difference in blood glucose levels (baseline vs. 3 months) after a weight management program and a significant difference in the change in HbAlc levels by mode of weight management intervention. Further analysis revealed that the ASPIRE phone-only group was the most effective mode of intervention.