Whole grain wheat sourdough bread does not affect plasminogen activator inhibitor-1 in adults with normal or impaired carbohydrate metabolism

Background and aimsEpidemiological studies suggest whole grain consumption is associated with a reduced risk of cardiovascular disease (CVD), possibly through alterations in glucose metabolism and subsequent effects on plasminogen activator inhibitor (PAI)-1, a novel biomarker for CVD. Our aim was to investigate the effect of 6 wk of whole grain wheat sourdough bread consumption versus refined white bread on PAI-1.Methods and ResultsNormoglycemic/normoinsulinemic (NGI; n = 14; age 53 ± 6 y; BMI 26.5 ± 2.9 kg/m²) and hyperglycemic/hyperinsulinemic (HGI; n = 14; age 57 ± 7 y; BMI 35.7 ± 5.7 kg/m²) adults incorporated whole grain wheat sourdough (162.5 g) or white (168.8 g) bread into their diet, for 6 wk in a randomized crossover study. Pre- and post-intervention, fasting blood samples were analyzed for PAI-1 (primary outcome), as well as glucose, insulin and glucagon (secondary outcomes) at fasting and postprandially after an oral glucose tolerance test (OGTT). Anthropometric measures, fasting glucose, insulin, glucagon and PAI-1 antigen and activity were not different between treatments in either NGI or HGI adults. Glucose incremental area under the curve (iAUC) was lower (19%, P = 0.02) after 6 wk consumption of whole grain wheat sourdough bread compared to white bread in the HGI group, with no differences in insulin or glucagon iAUC in either group.ConclusionOur data showed decreased glucose iAUC after an OGTT following 6 wk whole grain wheat bread consumption in adults with differing glycemic/insulinemic status, but no improvements in PAI-1 or fasting glycemic parameters.