Could stress during pregnancy lead to binge eating in daughters?
It is no secret that stress changes how we eat. We all have had a bad day and comforted ourselves with our favorite food or dessert.
Until now, this behavior has been assumed to be entirely psychological, but a new report suggests there may be more to the phenomenon and could shed light on why people with binge-eating disorder feel compelled to eat excessively in times of turmoil.
A team of researchers says their latest study on mice indicates binge eating behaviors brought on by stress may be brought on by heightened stress during late pregnancy. Particularly, female offspring of mice with high-stress conditions in late pregnancy showed unique brain wiring and binge-eating behaviors later in life.
Binge eating disorder is an eating disorder characterized by recurring episodes of consuming large amounts of food, especially when combined with a feeling of loss of control. For example, those with binge eating disorder may eat large amounts even when they feel full or not hungry.
Notably, women are statistically more likely to experience binge-eating disorder. This was also true in the study, where female offspring were particularly likely to exhibit binge-eating behaviors.
In their report published in the journal Cell Metabolism, researchers from the Weizmann Institute of Science in Israel and the Max Planck Institute of Psychiatry in Germany note that stress at or near birth is widely recognized to affect the fetus and predispose children to “various psychiatric and metabolic disorders.” They also explain that it is known this can affect males and females differently.
They also say that previous research shows that binge eating “has been associated to early-life stress such as childhood trauma and obstetric complications.”
To specifically show that stress in pregnancy is tied to binge eating, the researchers genetically engineered mice to manipulate their stress hormones. Specifically, the team focused on a circuit in the endocrine system called the corticotropin-releasing factor (CRF). Elevated levels of CRF are tied to increased anxiety, suppressed appetite, and inflammation. The researchers then triggered this circuit during the third trimester of pregnancy.
Initially, the offspring showed no abnormal eating behaviors. However, they found biological markers not found in healthy mice. Once one group was placed into a stressful situation, they immediately began to show binge eating behaviors.
The researchers restricted the eating periods for the mice to a 2-hour window only three times a week. During this time, the offspring with the genetic marker began to eat excessively. Meanwhile, another group of mice with the marker continued to eat normally with unlimited access to food.
The team admits that the study raises as many questions as it answers, but they believe it could open the door to a greater understanding of the biological mechanisms underlying conditions like binge eating disorder.
Senior co-author Alon Chen, neurobiologist at both the Weizmann Institute and the Max Planck Institute of Psychiatry says he hopes the findings will help others understand that eating disorders are based on biological phenomena: “The general public is less aware of the fact that we are dealing with a very biological mechanism that changes a person. People say, ‘Oh, it’s only in the brain.’ And yes, it’s in the brain. It involves changes in your genes, in your epigenome, and your brain circuits.”