Within-person compensation for snack energy by US adults, NHANES 2007–2014

Background: Most Americans snack and some snack several times a day; however, compensatory dietary and eating behaviors associated with snacking in free-living individuals are poorly understood. Objective: The aim of the study was to examine within-person differences in reported energy intake and eating patterns on a snack day relative to a no-snack day. Methods: We used 2 d of dietary recall data from the NHANES 2007-2014 to replicate the crossover nutrition study paradigm in a natural setting. Respondents reporting a snack episode in only one of two available dietary recalls were eligible for inclusion in the study (n=1,917 men and 1,860 women). We used multivariable regression methods to compare within-person differences in quantitative, qualitative, and eating pattern outcomes between the snack and nosnack recall days. Results: On the snack day, snack episodes provided (mean difference and 95% CI) 493 (454, 532) kcal of energy in men and 360 (328, 392) kcal in women. The 24-h energy intake on snack day was higher by 239 (140, 337) kcal in men and 219 (164, 273) kcal in women (P < 0.0001). On the snack day, both men and women were more likely to skip main meals and reported lower energy intake from main meals (P < 0.0001); however, the energy density of foods or beverages reported on the snack compared with no-snack days were not different. Fruit servings were higher on the snack day (P <= 0.0004), but intakes of vegetables and key micronutrients did not differ. The 24-h ingestive period was longer on the snack day (P < 0.0001). Conclusions: Free-living men and women partially compensated for snack energy by decreasing energy intake from main meals without adverse associations with qualitative dietary characteristics or time of meal consumption. Women compensated to a smaller extent than men. Thus, over the long term, snack episodes may contribute to positive energy balance, and the risk may be higher in women.