A US study found that when pregnant women follow nutritional guidelines, their exposure to many environmental chemicals from food and household products can be reduced. However, the authors warn that following a healthy diet rich in fruits and vegetables can also increase exposure to pesticides, and urge policy makers to include exposure to chemicals as a component of dietary guidelines.
Diet exposes consumers to environmental chemicals, which can enter food through farming, processing, packaging, storage, and preparation.
“What we found is that following the U.S. Dietary Guidelines may have two benefits: It helps meet nutritional needs during pregnancy, and it provides a way to reduce exposure to many common industrial chemicals,” said Dr. Diana Paciga, assistant professor at the University of Arizona.

This study was funded by the National Institutes of Health’s Environmental Effects on Child Health Outcomes (ECHO) program. The ECHO recently published research revealing that pregnant women are exposed to an average of 45 environmental chemicals. This led researchers to investigate how different dietary patterns are associated with chemical exposure.
“Reducing exposure to chemicals is especially important during pregnancy, as early ECHO studies have linked certain chemicals to poorer health outcomes for mothers and their children,” says study co-author Jesse Buckley, Ph.D., a professor in the Department of Epidemiology at the University of North Carolina’s Gillings School of Global Public Health.
Researchers found that pregnant women who followed the guidelines had less exposure to some chemicals commonly found in food packaging.Diet and chemicals during pregnancy
This research American Journal of Clinical Nutrition 1,500 pregnant women were included.
The researchers analyzed diet and chemical exposure and measured more than 100 chemicals and urine samples. The samples were then compared on how closely participants followed the American Dietary Guidelines.
Scientists found that pregnant women who followed the guidelines ate more lean protein and had less exposure to chemicals commonly found in food packaging and cooking byproducts.
Phthalates, which can leach into food from plastic packaging, were about 13% lower in pregnant women who ate a high-quality diet, the study found.
“Previous studies on diet and chemicals have identified specific food sources and broader dietary patterns associated with chemical exposure, but the evidence remains limited to well-studied chemicals. Food monitoring and observational studies have shown that consuming ultra-processed foods (foods high in saturated fat and added sugars, or packaged in plastic or cans) can increase exposure to phthalates and bisphenols.”
Researchers argue that fruits and vegetables can increase exposure to pesticides.Exposure to various foods
The authors emphasize that following dietary guidelines can also have negative effects, as certain fruits and vegetables can increase exposure to pesticides.
Consuming fewer added sugars and higher intakes of fruits, vegetables, and red meat protein in accordance with the guidelines was associated with both increased and decreased exposure to a variety of environmental chemicals. These findings highlight that dietary chemical exposure is a complex area to study.
“Fresh fruits and vegetables are important for a healthy diet during pregnancy, but they can also be a source of pesticides,” Paciga says. “By purchasing organic when possible and washing and peeling produce, you may be able to reduce your exposure while still eating these healthy foods.”
In a related recent study, scientists found traces of pesticides, antimicrobials and additives used in plastics and personal care products in breast milk samples from Canada and South Africa.
Researchers of the new study maintain that following nutritional guidelines is important for a healthy pregnancy, but add that the recent findings could shape future discussions about how exposure to environmental chemicals is included in dietary guidelines.
“Modest revisions to dietary guidelines that include advice to reduce exposure to chemicals could help protect the health of pregnant women without changing recommended foods that we already know support good nutrition,” Buckley says.

