Brain responses to food images during the early and late follicular phase of the menstrual cycle in healthy young women: relation to fasting and feeding

Abstract

Background: Food intake fluctuates throughout the menstrual cycle; it is greater during the early follicular and luteal phases than in the late follicular (periovulatory) phase. Ovarian steroids can influence brain areas that process food-related information, but the specific contribution of individual hormones and the importance of the prandial state remain unknown.

Objective: The objective was to examine whether brain activation during food visualization is affected by changes in estradiol concentration in the fasted and fed conditions.

Design: Nine eumenorrheic, lean young women [mean (±SD) age: 26.2 ± 3.2 y; body mass index (in kg/m(2)): 22.4 ± 1.2] completed 2 visits, one in the early (low estradiol) and one in the late (high estradiol) follicular phase of their menstrual cycle. At each visit, subjects underwent functional magnetic resonance imaging while they viewed food and nonfood images, before and after a standardized meal. Region-of-interest analysis was used to examine the effect of follicular phase and prandial state on brain activation (food > nonfood contrast) and its association with estradiol concentration.

Results: Differences were identified in the inferior frontal and fusiform gyri. In these areas, visualization of food elicited greater activation in the fed state than during fasting but only in the late follicular phase, when estradiol concentration was high. The change in estradiol concentration across the follicular phase (late minus early) was inversely correlated with the change in fusiform gyrus activation in the fasted state but not in the fed state.

Conclusion: Our findings suggest that estradiol may reduce food intake by decreasing sensitivity to food cues in the ventral visual pathway under conditions of energy deprivation. This trial was registered at clinicaltrials.gov as NCT00130117.

Figures

FIGURE 1

Region of interest (ROI) analysis. Brain activity in 3 ROIs [inferior frontal gyrus (A), fusiform gyrus (B), and insula (C)] in response to food > nonfood visualization throughout the 4 time points of the study (n = 9). A significant interaction between follicular phase (early/late) and prandial state (fasted/fed) was shown in the inferior frontal gyrus and fusiform gyrus. The insula showed a similar interaction effect of borderline significance. Prandial state affected activation (greater in the fed than in the fasted state) only during the late follicular phase. Columns represent mean parameter estimates (β values) ± SEMs, which are plotted for each ROI/time point. Brain maps (depicted in axial sections) highlight activation within each corresponding ROI for the paired comparison fed minus fasted (fed > fasted) during the late follicular phase (whole-brain analysis: thresholded at P < 0.005, uncorrected; for illustration purposes). L, left; R, right.

FIGURE 2

Association of brain activation with estradiol concentration. A: Change in estradiol concentration from early to late follicular phase correlated negatively with change in activity in the fusiform gyrus region of interest only during fasting (P = 0.013). Solid and dashed lines indicate the correlation lines for fasting (▪) and fed (○), respectively. B: Brain coronal sections depict the areas that showed a positive (red) and negative (blue) significant correlation with estradiol elevation from the early to the late follicular phase in the whole-brain analysis (contrast food > nonfood; P < 0.05, corrected).