Many women have wondered whether hormonal birth control affects their mood, appetite or cravings. A new study suggests that, for some women, combined oral contraceptive pills may also be linked with changes in emotional eating.
The study, published in JAMA Network Open, followed 422 women taking combined oral contraceptives, which contain synthetic estrogen and progestin. Researchers tracked participants for 49 consecutive days and compared symptoms during active hormone pills with symptoms during inactive, hormone-free pills. They found that emotional eating symptoms were higher during active pill days.
The study does not show that birth control pills cause binge eating disorder. It also does not mean combined oral contraceptives are unsafe for most women or that anyone should stop taking them based on this finding alone. Instead, the results suggest that hormone shifts from active pills may affect eating-related symptoms for some women, especially those who may already be vulnerable.
“These findings are important for highlighting the potential negative impact of combined oral contraceptives in women. Nonetheless, it’s important to note that not every woman in the study developed binge eating — they are safe for many women, and it’s likely that the risk is targeted to those with other risk factors,” said Kelly Klump, lead author of the study and MSU Research Foundation Distinguished Professor in MSU’s Department of Psychology. “Future studies are needed to better identify who is at risk and inform personalized medicine approaches to women’s health.”
The study focused on emotional eating, which the researchers described as a form of binge-related eating in which people overconsume food in response to negative emotions. That is not the same as saying every participant had binge eating disorder, a clinical diagnosis with specific criteria.
The study design allowed researchers to compare changes within the same women across different pill phases. Combined oral contraceptives typically include active pills containing synthetic hormones and inactive pills that do not contain hormones. By tracking daily symptoms across both phases, researchers could look at whether binge-related symptoms changed when women were taking active hormone pills.
The researchers found significantly higher emotional eating during active pills compared with inactive pills. The pattern appeared in the full group of participants and among women who reported current or past clinical levels of binge eating.
Previous research has suggested that natural ovarian hormones, including estrogen and progesterone, may influence binge-eating risk in females. This study adds a new question: whether synthetic hormones in combined oral contraceptives may also affect binge-related symptoms for some women.
That does not mean all hormonal birth control has the same effect. The study looked at combined oral contraceptive pills, not progestin-only pills, hormonal IUDs, implants, shots, patches, rings or nonhormonal methods. The findings should not be stretched to every form of contraception.
The study also found a potentially useful tool. Participants’ binge-eating symptoms decreased over the study period as they reported on their eating each day. The researchers described that daily reporting as self-monitoring.
“We found that self-monitoring was an effective tool in mitigating risk for women in the study,” Klump said. “The more we can equip women with tools and educate medical providers about these risks, the more effective care can be given.”
Self-monitoring can mean paying closer attention to patterns, such as whether emotional eating symptoms seem to change at certain points in a menstrual cycle, pill pack or stressful period. For some people, that kind of tracking may help them notice changes earlier and discuss them with a health care provider.
Still, self-monitoring is not the right tool for everyone. For people with a history of eating disorders or obsessive tracking, monitoring food or symptoms can sometimes become stressful or counterproductive. In those cases, support from a clinician, therapist or dietitian may be especially important.
The most practical message from the study is not that women should fear birth control pills. It’s that side effects can vary from person to person, and eating-related symptoms may be worth including in conversations about contraception.
For someone who notices a change in emotional eating, binge-eating symptoms, mood or appetite after starting or changing birth control, the next step is not to stop suddenly. Stopping contraception without a plan can increase the chance of unintended pregnancy and may not address the underlying symptoms. A better option is to talk with a clinician about the timing of symptoms, medical history, eating-disorder risk and whether another contraceptive approach might be a better fit.
The study points toward a more personalized approach to women’s health, one that takes eating behavior seriously and recognizes that the same medication may not feel the same for everyone.
The research was supported by the National Institute of Mental Health. The grant provided salary support for several authors and financial support for the design and conduct of the study, as well as collection, management and analysis of the data. Additional support came from a National Institute of Mental Health grant and National Science Foundation Graduate Research Fellowships.