Exposure to endocrine-disrupting chemicals in early life, including during gestation and infancy, results in a higher preference for sugary and fatty foods later in life, according to an animal study being presented Sunday at ENDO 2025, the Endocrine Society’s annual meeting in San Francisco, Calif.

Endocrine-disrupting chemicals are substances in the environment (air, soil or water supply), food sources, personal care products and manufactured products that interfere with the normal function of the body’s endocrine system. To determine if early-life exposure to these chemicals affects eating behaviors and preferences, researchers from the University of Texas at Austin conducted a study of 15 male and 15 female rats exposed to a common mixture of these chemicals during gestation or infancy.

“Our research indicates that endocrine-disrupting chemicals can physically alter the brain’s pathways that control reward preference and eating behavior. These results may partially explain increasing rates of obesity around the world,” said Emily N. Hilz, Ph.D., a postdoctoral research fellow at the University of Texas at Austin in Austin, Texas.

“Understanding the harmful health impact that exposure to these types of chemicals can have on eating patterns may help inform public health recommendations and personal efforts to improve diet-related health complications.”

Researchers administered behavioral studies throughout the rats’ lifespans, including into adulthood, to observe preferences for high-fat foods and a sucrose solution. Findings showed that male rats with early-life exposure to endocrine-disrupting chemicals had a temporary preference for the sucrose solution, while female rats showed a strong preference for high-fat food that resulted in weight gain. In addition, testosterone was reduced in exposed males, while estradiol in females remained unchanged.

During the study, areas of the brain were sequenced to determine if early-life exposure to endocrine-disrupting chemicals resulted in physical changes to the regions important to controlling food intake and responding to reward. Researchers observed changes to gene expression throughout all areas sequenced in male rat brains, and varying changes to gene expression in the region of female rat brains associated with reward. These physical changes were predictive of changes to eating behavior and food preferences.

“It’s important that people understand that there are negative impacts associated with consuming or being near endocrine-disrupting chemicals early in life. With this knowledge in hand, consumers may want to consider reducing personal interaction with environments, food and other types of products containing these chemicals during pregnancy and early childhood to reduce the risk of developing obesity later in life,” Hilz added.

The study is titled “Epigenetic and transcriptional changes associated with early-life exposure to a mixture of endocrine-disrupting chemicals: obesogenic effects in the brain reward system,” and it will be presented Sunday, July 13.