Inverse relationship between dietary fiber intake and environmental exposure to acrylamide

Dietary fiber intake was thought to decrease some environmental pollutant exposure by increasing gastrointestinal excretion. While diet is considered the major source of exposure to acrylamide (AA), the impact of dietary fiber intake on acrylamide (AA) exposure is still unknown. We analyzed the associations between dietary fiber intake and AA hemoglobin biomarkers [hemoglobin adducts of acrylamide (HbAA) and glycinamide (HbGA), and sum of HbAA and HbGA (HbAA + HbGA)] among 3448 US adults who participated in the National Health and Nutrition Examination Survey (NHANES) 2013-2016. Multivariable linear regression and cubic spline models were conducted to estimate the associations between dietary fiber intake and AA hemoglobin biomarkers. Dietary fiber intake had a strong inverse and J-shaped association with AA hemoglobin biomarkers. In the fully adjusted linear regression model, compared with participants in the lowest dietary fiber quantile, the adjusted percent change with 95% confidence intervals (CIs) in HbAA for the highest dietary fiber quantile was - 19.7% (- 26.7%, - 13.1%); for HbGA, it was - 12.2% (- 18.9%, - 4.9%), and for HbAA + HbGA, it was - 17.3% (- 23.7%, - 10.4%). Associations between higher dietary fiber intake and lower levels of environmental exposure to acrylamide hemoglobin biomarkers suggest the need to increase dietary fiber intake.