The interactive effects of estrogen and progesterone on changes in emotional eating across the menstrual cycle

Abstract

Studies suggest that within-person changes in estrogen and progesterone predict changes in binge eating across the menstrual cycle. However, samples have been extremely small (maximum N = 9), and analyses have not examined the interactive effects of hormones that are critical for changes in food intake in animals. The aims of the current study were to examine ovarian hormone interactions in the prediction of within-subject changes in emotional eating in the largest sample of women to date (N = 196). Participants provided daily ratings of emotional eating and saliva samples for hormone measurement for 45 consecutive days. Results confirmed that changes in ovarian hormones predict changes in emotional eating across the menstrual cycle, with a significant estradiol × progesterone interaction. Emotional eating scores were highest during the midluteal phase, when progesterone peaks and estradiol demonstrates a secondary peak. Findings extend previous work by highlighting significant interactions between estrogen and progesterone that explain midluteal increases in emotional eating. Future work should explore mechanisms (e.g., gene-hormone interactions) that contribute to both within- and between-subjects differences in emotional eating.

Figure 1. Emotional Eating, Estradiol, and Progesterone across the Menstrual Cycle

Mean Z Score = the mean of the 5-day rolling averages calculated within subjects, then averaged across participants; T = transition days that are in-between phases. Mean values within each phase are included for descriptive purposes only, as the daily z scores were included in the mixed linear models for each phase contrast. Mean values for emotional eating z scores (with non-z scored, within-person centered means in parentheses) in each phase are: Follicular: M = 0.03 (.001), SD = 1.11, Ovulatory: M = -0.11 (-.02), SD = 0.98; Mid-luteal: M = 0.05 (.01), SD = 0.93; Premenstrual: M = -0.05 (-.003), SD = 0.82. The number of days included in each phase varied by participant based on their cycle length, but the days roughly corresponded to the following (first day of menstrual bleeding = +1; previous day = -1): Follicular = +3 to +12; Ovulatory = -15 to -12; Mid-luteal = -9 to -5; Premenstrual = -3 to +1.

Figure 2. Interactions between Estradiol and Progesterone in the Prediction of Emotional Eating in the a) Full Sample, b) Top 33% of Scorers, and c) Top 10% of Scorers

“Emotional Eating Z Score” = 5-day rolling average calculated within subjects, then averaged across participants.