Whole- and refined-grain intakes are differentially associated with abdominal visceral and subcutaneous adiposity in healthy adults: the Framingham Heart Study.

BACKGROUND: Observational studies have linked higher intakes of whole grains to lower abdominal adiposity; however, the association between whole- and refined-grain intake and body fat compartments has yet to be reported.

OBJECTIVE: Different aspects of diet may be differentially related to body fat distribution. The purpose of this study was to assess associations between whole- and refined-grain intake and abdominal subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT).

DESIGN: Cross-sectional associations between whole- and refined-grain intakes, waist circumference measures, and abdominal SAT and VAT volumes were examined in 2834 Framingham Heart Study participants (49.4% women; age range: 32-83 y). Dietary information was assessed with the use of a semiquantitative food-frequency questionnaire.

RESULTS: Whole-grain intake was inversely associated with SAT (2895 compared with 2552 cm³ in the lowest compared with the highest quintile category, P for trend < 0.001) and VAT (1883 compared with 1563 cm³, P for trend < 0.001), after adjustment for age, sex, current smoking status, total energy, and alcohol intake. In contrast, refined-grain intake was positively associated with SAT (2748 compared with 2934 cm³, P for trend = 0.01) and VAT (1727 compared with 1928 cm³, P for trend < 0.001) in multivariable models. When SAT and VAT were evaluated jointly, the P value for SAT was attenuated (P = 0.28 for whole grains, P = 0.60 for refined grains), whereas VAT remained associated with both whole grains (P < 0.001) and refined grains (P < 0.001).

CONCLUSIONS: Increasing whole-grain intake is associated with lower VAT in adults, whereas higher intakes of refined grains are associated with higher VAT. Further research is required to elicit the potential mechanisms whereby whole- and refined-grain foods may influence body fat distribution.