A new study published in JAMA Network Open on Jul. 6 found that emotional eating was significantly higher during days when women took hormone-containing birth control pills compared to hormone-free days. The research followed 422 women who were already using combined oral contraceptives, tracking their daily eating patterns for 49 consecutive days.
The study aimed to determine whether binge-related eating changes depending on the use of active (hormone-containing) versus inactive (hormone-free) pills within a typical birth control cycle. In most packs, about three weeks consist of active pills and one week of inactive pills.
"Because we tracked the same women day to day, we could see how eating changed with hormone exposure," said Dr. Shaunna Clark, a co-author and associate professor of psychiatry and behavioral sciences at Texas A&M University's Naresh K. Vashisht College of Medicine.
Researchers used a within-person design, meaning each participant served as her own comparison point over time. Emotional eating was measured while noting whether each day corresponded to an active or inactive pill. The results showed that emotional eating increased during periods when participants were exposed to hormones from the active pills.
Clark said these findings remained even after accounting for negative mood, suggesting that "the hormones themselves may be playing a role, rather than those changes being driven by mood or other factors." She also noted that while the pattern appeared at the group level, individual responses varied: "These findings show a pattern at the group level," she said, "but individual responses can vary." The analysis focused on young adult women using monophasic combined oral contraceptives providing consistent hormone doses during active pill days.
The study does not establish causation between birth control use and binge eating, but identifies an association between hormone exposure and increased emotional eating within individuals. Researchers also tested other outcomes but found the effect specific to binge-related behavior rather than general shifts in mood or body image concerns.
