Previously, consumption of wholegrain foods has been related to a more nutrient dense diet in Irish adults( Reference Devlin, McNulty and Walton 1 ). This analysis investigated any associations between eating wholegrain foods and biomarkers of nutritional status using data from the National Adult Nutrition Survey (2008–2010) (www.iuna.net) ( 2 ). A 4-day semi-weighed food diary recorded food intake data of 1500 adults and wholegrain intake was identified at food and brand level( Reference Devlin, McNulty and Walton 1 ). Markers of nutritional status were measured by ELISA (serum 25(OH) vitamin D), microbiological assay (red blood cell (RBC) and serum folate), fluorescence polarization immunoassay (plasma homocysteine; Hcy), HPLC (plasma pyridoxal-5′-phosphate; PLP, vitamin B6), erythrocyte glutathione reductase activation coefficient (EGRAC; riboflavin), Beckman Coulter Counter (Haemoglobin; Hb) or a RX Daytona automated analyser (serum ferritin, Total Iron Binding Capacity; TIBC). After the exclusion of under-reporters, non-consumers of whole grain were identified and tertiles of intake calculated for consumers.
* Differences between groups were determined by General Linear Model with Bonferroni post hoc tests on log transformed variables where applicable; controlling for social class, supplement use, gender, age, alcohol intake, smoking and energy intake. Different subscripted letters indicate statistically significant (P < 0·05) differences between groups.
Higher dietary wholegrain intakes were associated with improvements in B-vitamin and homocysteine status but not in biomarkers of iron or vitamin D intake. Across the consumption groups, there were no changes (P > 0·05) in dietary intakes (mg or μg/10MJ/day) of iron, vitamin D or of any of the B vitamins studied. Although correlations were weak, dietary intakes of wholegrain containing breads, ready to eat breakfast cereals and cooked breakfast cereals were more strongly (P < 0·05) related with B-vitamin and homocysteine status than other wholegrain containing foods. Further research will identify whether benefits of eating wholegrain containing foods exist beyond B-vitamin status.
The project was funded by the Irish Department of Agriculture, Food and the Marine under the Nutridata Project 13 F 542; 2014–2016.
