Summary: A large new study has found a direct association between combined oral contraceptive (COC) use and short-term increases in binge-related symptoms, particularly emotional eating. Tracking 422 women from the Michigan State University Twin Registry across 49 consecutive days, researchers compared behavior during weeks when participants took active hormone pills (containing synthetic estrogen and progestin) with weeks when they took inactive placebo pills. Emotional eating—overeating in response to negative emotions—was significantly higher during active pill phases.
The rise in emotional eating was evident across the entire sample and among the subgroup who reported clinical histories of binge eating, but it was not universal. The increased vulnerability linked to synthetic hormones appeared concentrated in women with preexisting genetic, biological, or clinical risk factors. Importantly, the study also found that a simple behavioral step—daily self-monitoring of eating and emotions—substantially reduced binge-eating episodes, even during active hormone phases.
Key Facts
- Synthetic hormone association: Combined oral contraceptives that contain synthetic estrogen and progestin were associated with elevated emotional eating during active-pill use compared with inactive-pill (placebo) weeks.
- First large-scale, daily tracking study: This is the first comprehensive longitudinal study to measure day-to-day changes in binge-related symptoms across active and inactive COC pill phases in a large cohort.
- Study cohort and duration: The research followed 422 women from the Michigan State University Twin Registry over 49 consecutive days to capture within-person changes across pill cycles.
- Targeted risk: Not all contraceptive users experienced increased symptoms—heightened risk was concentrated among women with existing vulnerability to disordered eating.
- Effective low-cost intervention: Daily self-reporting and monitoring of eating and mood served as a practical psychological intervention that reduced symptom spikes linked to active hormone pills.
- Implications for personalized care: Study authors urge educating clinicians about these neurobehavioral effects so contraceptive choices can be more individualized.
Source: Michigan State University
Overview of the study
Researchers recruited women already using monophasic combined oral contraceptives and collected daily reports about pill type (active versus inactive) and emotional eating for 49 straight days. The design took advantage of routine birth-control packs that include both hormone-containing active pills and hormone-free placebo pills, allowing within-person comparisons that reduce confounding from stable individual differences.
Over the monitoring period, emotional eating increased significantly during active-pill weeks compared with inactive weeks. These within-person increases persisted after controlling for negative mood and were observed across two consecutive pill cycles, indicating a replicable pattern. Weight preoccupation, a different outcome historically unrelated to ovarian hormone fluctuations, did not change across pill phases, supporting the specificity of the finding for emotional eating.
Lead author Kelly Klump, MSU Research Foundation Distinguished Professor in the Department of Psychology, emphasized that while these results highlight a potential negative effect of combined oral contraceptives for some women, COCs remain safe and effective for many users. She and the team stress that the elevated risk is likely concentrated among women with other biological or psychological vulnerabilities.
The study also documented a clear, clinically relevant mitigation strategy: participants who completed daily self-monitoring of their eating and emotional states experienced meaningful reductions in binge-eating behaviors, even during active hormone phases. Self-monitoring is a core component of cognitive-behavioral approaches and appears to interrupt automatic, hormone-driven impulses by increasing awareness and engaging cognitive control processes.
Questions addressed by the research
A: Natural ovarian hormones such as estrogen and progesterone interact with brain systems that regulate reward, mood, and appetite. Combined oral contraceptives introduce synthetic hormone variants that override natural cycles and can alter those neural pathways. For individuals already vulnerable to disordered eating, these exogenous hormones may disrupt appetite regulation and increase the likelihood of using food to cope with negative emotions.
A: No. The results do not indicate that COCs universally cause binge eating or eating disorders. Instead, COCs may act as one environmental or biological trigger that increases risk in a specific subset of women who have underlying susceptibilities. Most users will not experience clinically significant problems.
A: Daily tracking increases self-awareness and creates a pause between impulsive urges and behavior. By recording emotions and food intake, people engage cognitive control mechanisms that counteract automatic responses. This process, central to cognitive-behavioral interventions, helps individuals recognize hormonal fluctuations without automatically turning to overeating.
Editorial notes
- This piece was edited by an editor at Neuroscience News.
- The original journal paper was reviewed in full by staff.
- Additional explanatory context was added by the reporting team.
About this research
Author: Jack Harrison
Source: Michigan State University
Contact: Jack Harrison – Michigan State University
Image credit: Neuroscience News
Original research (open access): “Combined Oral Contraceptive Use and Binge Eating” by Klump KL, Di Dio AM, Anaya C, Mikhail ME, Burt SA, Sisk CL, Keel PK, Katzman DK, Neale M, Ackerman LS, Clark SL, Culbert KM. JAMA Network Open. DOI: 10.1001/jamanetworkopen.2026.19047
Abstract
Combined Oral Contraceptive Use and Binge Eating
Importance
Prior work indicates that natural ovarian hormones influence binge-eating risk in females. Because roughly 85% of women use combined oral contraceptives that simulate hormonal states associated with elevated binge-eating risk, it is important to understand whether COCs affect disordered eating behaviors.
Objective
To examine within-person associations between active versus inactive combined oral contraceptive pills and binge-related eating, measured as emotional eating.
Design, Setting, and Participants
This population-based longitudinal survey collected daily reports from women in the Michigan State University Twin Registry across 49 consecutive days, comparing active versus inactive pill use and day-to-day emotional eating. Data were gathered from 2017 to 2024 and analyzed from April 2024 to November 2025. The full sample included 422 women; a subsample of 51 women reported clinically defined binge-eating episodes.
Exposure
Type of pill (active hormone pill vs inactive placebo pill).
Main Outcomes and Measures
Primary outcome was within-person change in emotional eating between inactive and active pill phases, controlling for negative affect. Analyses also examined weight preoccupation as a control outcome and replicated effects across two pill cycles.
Results
Among 422 women (mean age ~22 years), emotional eating increased significantly during active-pill weeks compared with inactive weeks across both cycles. These effects were not explained by concurrent changes in negative mood and were also present in the clinically affected subsample. Weight preoccupation did not vary by pill phase, underscoring the specificity for emotional eating.
Conclusions and Relevance
Daily monitoring revealed a specific association between active combined oral contraceptive pills and elevated risk for emotional eating. Future research should clarify which women are most vulnerable and inform personalized contraceptive choices to minimize impacts on eating behavior.