Biological Response to Meal Ingestion: Gender Differences

Abstract

In a previous study, we demonstrated that women enjoyed and tolerated lower meal loads than men. Hence, we hypothesized that with the same meal load, their postprandial response is more pronounced than in men. We performed a randomized parallel trial in 12 women and 12 men comparing the postprandial responses to a palatable comfort meal. We measured homeostatic sensations (hunger/satiety, fullness) and hedonic sensations (digestive well-being, mood) on 10 cm scales, vagal tone by heart ratio variability and the metabolomic profile before and after meal ingestion. Gender differences were analyzed by repeated measures ANCOVA. Overall (n = 24), ingestion of the probe meal induced satiation, fullness, digestive well-being and improved mood (main time-effect p ≤ 0.005 for all). Women exhibited a more intense sensory experience, specially more postprandial fullness, than men [main gender-effect F (1, 21) = 7.14; p = 0.014]; hedonic responses in women also tended to be stronger than in men. Women exhibited more pronounced effects on vagal tone [main gender-effect F (1, 21) = 5.5; p = 0.029] and a different lipoprotein response than men. In conclusion, our data indicate that gender influences the responses to meal ingestion, and these differences may explain the predisposition and higher incidence in women of meal-related functional disorders.

Keywords: gender differences; hedonic response; homeostatic response; meal ingestion; metabolomic response; postprandial sensations.

Figure 1

Postprandial experience in women and men. Main gender-effect by repeated measures ANCOVA shown; dependent variable: postprandial scores; covariate: pre-meal scores. Temporal responses to meal ingestion analyzed by one-way ANOVA for repeated measures; asterisks indicate significant differences from premeal values by post-hoc comparisons (p < 0.05 applying the Sidak correction procedure for multiple comparisons). Postprandial sensations tended to be higher in women than in men, but the differences in satiety and digestive well-being were blurred because the scores were near the top of the scales in both groups.

Figure 2

Physiological responses to probe meal. Data are postprandial changes from premeal baseline (mean ± SE). Overall, meal ingestion was associated with an increase in diastolic blood pressure, heart rate and vagal tone (main time-effect p ≤ 0.003 for all; n = 24). As compared to men, women exhibited more pronounced effects on heart rate and vagal tone (by ANCOVA).

Figure 3

Lipidic response to meal ingestion. Meal ingestion induced changes in the profile of plasma lipoproteins with differences between women and men. Dara are means ± SE.