(P20-005-23) Exploring the Relationship Between Blood Lead Levels on Gut Microbiome Diversity Using the Phytoestrogens Enterodiol and Enterolactone As Biomarkers

Objectives: The phytoestrogens enterolactone and enterodiol have been proposed as possible biomarkers to measure gut microbiome diversity. Diversity in the gut’s flora creates a more stable environment and is associated with systemic health benefits. This stability can be altered by a myriad of factors including heavy metal exposure. Lead is a known toxic heavy metal that can impact the microbiome’s flora and potentially the production of enterolactone and enterodiol. The aim of this study is to determine if the phytoestrogens enterolactone and enterodiol are impacted by blood lead levels.

Methods: Data from the 2009-2010 NHANES was exported and analyzed in SPSS. The correlation between enterodiol and enterolactone with blood lead levels were analyzed using weighted multiple linear regression for participants between the ages of 18 and 50. BMI and fiber intake were included in the model to control their potential influence on microbiome diversity. A p value of < .05 was used to determine significance.

Results: A total of 1029 participants were included in the secondary data analysis. An R square of 0.011 was calculated for the regression model to predict enterodiol concentration in the urine. There was no significant correlation between lead (p = 0.164), BMI (p = 0.074), or fiber intake (p = 0.139) and enterodiol. An R square of 0.041 was calculated for the regression model to predict enterolactone concentrations in the urine. There was a significant negative correlation between lead levels (p=0.018) and BMI (p=0.01) and enterolactone. There was a significant positive correlation between fiber intake and enterolactone (p=0.002).

Conclusions: Enterodiol concentrations are not significantly impacted by lead, BMI, or fiber intake. Lead exposure, BMI, and fiber intake account for 4.1% of the variability in concentrations of enterolactone in urine. This accounts for a small percentage of the variability but is logical because the diversity of the gut microbiome can be impacted by numerous factors. There is a significant negative correlation between lead exposure and enterolactone. This suggests that lead decreases the gut microbiome’s diversity, resulting in the reduction of the population of bacterial species involved with the synthesis of enterolactone but not enterodiol.

Funding Sources: Florida International University's Department of Nutrition and Dietetics