Physical activity is a confounding factor of the relation between eating frequency and body composition

BACKGROUND: It has been shown that eating frequency (EF) is related to body composition in women, but the results are inconclusive. These inconsistent findings could be due to the influence of additional factors such as physical activity. OBJECTIVE: We aimed to investigate the relation between EF and body composition in premenopausal women and to explore the effect of physical activity energy expenditure (PAEE) and physical fitness on that association. DESIGN: Eighty-five premenopausal women [x ± SD age: 49.9 ± 2.0 y; body mass index (in kg/m²): 23.2 ± 2.2] were studied at the onset of a prospective observational study. Seven-day food diaries were used to measure energy intake and EF. Body composition (measured with dual-energy X-ray absorptiometry), physical fitness (measured by the peak oxygen consumption), and PAEE (measured by using an accelerometer) were also measured. RESULTS: Mean EF was 4.6 ± 0.9 eating occasions/d. A significant positive correlation was found between EF and energy intake (r = 0.31, P < 0.01). Moreover, EF was negatively correlated with body mass index (r = -0.25, P < 0.05), waist circumference (r = -0.32, P < 0.01), percentage body fat (r = -0.26, P < 0.05), and fat mass (r = -0.27, P < 0.05). The associations between adiposity and EF were no longer significant after correction for PAEE and peak oxygen consumption. CONCLUSION: The relation between EF and body composition could be mediated by PAEE and physical fitness.