Consumption of whole purple and regular wheat modestly improves metabolic markers in adults with elevated high-sensitivity C-reactive protein: A randomised, single-blind parallel-arm study

Whole grain wheat, in particular colored varieties, may have health benefits in adults with chronic metabolic disease risk factors. In this intervention study, 29 overweight and obese adults with chronic inflammation consumed four daily servings of bran-enriched purple or regular whole wheat convenience bars which replaced their consumption of refined grain food products for 8 weeks in a randomized, single-blind parallel arm study where body weight was maintained. Anthropometrics, blood markers of inflammation, oxidative stress, and lipemia and metabolites of anthocyanins and phenolic acids were compared at Days 1, 29 and 57 using repeated measures analysis of variance within groups and analysis of covariance between groups at Day 57, with Day 1 as a covariate. A significant reduction in the inflammatory marker interleukin-6 and increase in adiponectin (a hormone that is involved in regulating glucose and fatty acid breakdown) were observed within the purple wheat (PW) group. Tumor necrosis factor (TNF)-α, an inflammatory marker, was lowered in both groups, and ferulic acid (a potent antioxidant) increased in the regular wheat (RW) group. Comparing between wheats, only plasma TNF-α and glucose differed significantly (P<0.05), i.e. TNF-α and glucose decreased with RW and PW, respectively. Consumption of PW or RW products showed potential to improve plasma markers of inflammation and oxidative stress in participants with evidence of chronic inflammation, with modest differences observed based on type of wheat. The study demonstrates the importance of wholegrain foods in our diets especially colored grains.