Exposure to Lead Increases Obesity Risk in Mice

A new study suggests that exposure to lead can increase the risk of obesity.

Researchers from the University of Michigan conducted a study and found that even at low levels, lead increased obesity risk in mice.

Lead is known to raise the risk of neurological problems in humans. The scientists say that their study shows that the metal could even increase risk of several chronic health conditions. What's more is that the research even found that the effect of lead exposure is passed down from females to their progeny.

"The data support the obesogen hypothesis that toxicant exposures in the womb contribute to the higher rate of obesity," said Dana Dolinoy, the senior author of the study, according to a news release. "There are certain chemicals that are considered the hallmarks of the obesity epidemic, and lead has not been not one of them."

For the study, female mice were exposed to lead via drinking water two weeks before mating and then throughout pregnancy and nursing. Their babies were then measured at 3, 6 and 9 months of age for their activity levels and food intake.

The researchers found that both male and female offspring of mothers exposed to high levels of lead were more likely to eat more food than others. These mice also had a higher risk of developing obesity.

Lead exposure in the study varied from 0.0 parts per million (ppm) for the control group, 2.1ppm, 16ppm to 32ppm.

Maternal blood lead levels for control group couldn't be detected. The lead levels for other groups were 4.1 (±1.3) micrograms per deciliter (μg/dL), 25.1 (±7.3) μg/dL and 32.1 (±11.4) μg/dL

The Centers for Disease Control and Prevention has established that children with 5 μg/dL or more of lead in blood need monitoring. However, the agency hasn't given a reference point for maternal blood lead levels.

The present study shows that children of mothers exposed to lead might also be at a risk of developing obesity.

"To see that the level I and others have considered very low has such statistical significance in this study is alarming. There is no minimum safe level for lead. Our research really supports this," said Christopher Faulk, research fellow in the Dolinoy Lab-Environmental Epigenetics and Nutrition.

The study is published in the journal PLOS-ONE.