Exposure to Dioxins May Increase Obesity Risk

TOPLINE:

Combined exposure to dioxins and dioxin-like polychlorinated biphenyls (DL-PCBs) is significantly associated with an increased risk for obesity in adults, with 1,2,3,4,6,7,8-heptachlorodibenzo-p-dioxin (HpCDD) showing the greatest contribution.

METHODOLOGY:

• Recent evidence has shown that environmental contaminants, particularly dioxins and dioxin-like polychlorinated biphenyls, may be linked to an increased risk for obesity as endocrine-disrupting chemicals.
• Researchers evaluated the relationship between mixed exposure to nine types of dioxins and DL-PCBs and obesity or obesity indices in 852 adults using data from the National Health and Nutrition Examination Survey from 2003 to 2004.
• They chose nine chemicals for analysis: 1,2,3,4,6,7,8-HpCDD; 1,2,3,4,6,7,8,9-octachlorodibenzo-p-dioxin (OCDD); 3,3’,4,4’,5-pentachlorodibenzofuran (PnCB); PCB28; PCB66; PCB74; PCB105; PCB118; and PCB156.
• General and abdominal obesity were present in 34% and 53.9% of participants, respectively.
• Multiple statistical approaches were employed to evaluate the association of exposures to dioxins and DL-PCBs with obesity. Mediation analysis was performed to assess the potential role of A1c in this association.

TAKEAWAY:

• Multivariable logistic regression analysis found that a single exposure to higher concentrations of 1,2,3,4,6,7,8-HpCDD; 1,2,3,4,6,7,8,9-OCDD; 3,3’,4,4’,5-PnCB; PCB74; PCB105; and PCB118 was associated with an increased risk for general and abdominal obesity (P for trend 
• Combined exposure to dioxins and DL-PCBs was positively associated with the risk for obesity, with 1,2,3,4,6,7,8-HpCDD showing the greatest contribution.
• When considering obesity indices, 1,2,3,4,6,7,8,9-OCDD; 1,2,3,4,6,7,8-HpCDD; 3,3’,4,4’,5-PnCB; PCB74; PCB105; and PCB118 were significantly associated with body mass index and waist circumference.
• A1c levels significantly mediated the association between mixed exposure to dioxins and DL-PCBs and obesity (P

IN PRACTICE:

“Our findings suggested that dioxins and DL-PCBs may be independent risk factors for obesity,” the authors wrote. “The hazards of dioxins on obesity should be emphasized, and additional studies are desirable to elucidate the potential mechanisms for dioxins on obesity in adults.”

SOURCE:

This study, led by Zhao-Xing Gao, Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University and Center for Big Data and Population Health of IHM, both in Hefei, China, was published online in The Journal of Clinical Endocrinology & Metabolism.

LIMITATIONS:

The cross-sectional nature of this study prevented the establishment of causal relationships between dioxins or DL-PCBs and obesity. This study relied on a small sample. Replacing chemical concentrations below the limit of detection with fixed values may have introduced bias.

DISCLOSURES:

This study was funded by grants from the National Natural Science Foundation of China, Research Fund of Anhui Institute of Translational Medicine, and Research Fund of Center for Big Data and Population Health of IHM. The authors declared no conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.