Sandwich consumption in relation to daily dietary intake and diet quality among US adults, 2003–2012

Abstract

ObjectivesAbout one half of the US adult population consumed one or more sandwiches on any given day. Sandwich consumption may profoundly influence people's calorie intake and diet quality. However, few studies have investigated the nutritional impact of sandwich consumption at the national level. We examined sandwich consumption in relation to daily dietary intake and diet quality among US adults. Study designRetrospective data analysis. MethodsNationally representative sample consisting of 27,075 adults 18 years of age and above came from the National Health and Nutrition Examination Survey (NHANES) 2003–2012 waves. Sandwich consumption was identified based on the What We Eat in America Food Category and the NHANES diet combination code. First-difference estimator addressed confounding bias from time-invariant unobservables (e.g. eating habits, taste preferences) by using within-individual variations in sandwich consumption between two non-consecutive 24-h dietary recalls. ResultsDuring 2003–2012, approximately 53.2% of US adults consumed sandwiches on any given day. Among sandwich consumers, nearly a quarter of daily total calorie intake and about a third of total fat, saturated fat, cholesterol, and sodium intake came from sandwich consumption. Men, non-Hispanic whites, young and middle-aged adults, people with higher income, and overweight/obese adults were more likely to consume sandwiches. Among those who consumed sandwiches on either but not both of the two dietary recall days, in comparison to no sandwich consumption, sandwich consumption on a dietary recall day was associated with an increase in daily intake of total energy by 98.7 kcal, total fat 6.8 g, and sodium 267.9 mg (P-value < 0.001). Statistically significant but relatively small differences were also found for other nutrients and food groups—sandwich consumption was associated with an increase in daily intake of sugar by 3.0 g (P-value < 0.01) and saturated fat 2.5 g (P-value < 0.001), a decrease in daily intake of vegetables by 8.4 g (P-value < 0.01), fruit 4.5 g (P-value < 0.05), and fibre 0.8 g (P-value < 0.001), and a decrease in the Healthy Eating Index-2010 score by 1.6 points (P-value < 0.001). ConclusionsConsumers should prudently evaluate the calorie/nutrient content of sandwich in order to make healthier dietary choices.