The typical Mexican diet includes beans and tortillas, which are foods with a low glycemic index. The objective of this paper was to compare the effects of a lower and a higher glycemic index Mexican style diet on metabolic control. In a randomized, controlled crossover design, eight subjects with type 2 diabetes were assigned to either a high glycemic index (GI=72), lower dietary fiber (30g/d) diet or a moderate glycemic index (GI=60) higher dietary fiber (53g/d) for three weeks each. Biochemical data was obtained at the start and finish of each dietary period. Multi and univariate one-factor repeated-measures analysis of variance was used to compare biochemical data. The overall differences in the total and LDL cholesterol (5.02 +/- 0.6 to 3.36 +/- 0.83) population means were significant (P<0.004 and P<0.001). We conclude that a low GI diet with more than 23g fiber per day, containing Mexican style foods may help to improve dyslipidemia in individuals with type 2 diabetes. (C) 2004 Elsevier Inc. All rights reserved.