Underreporting in self-reported dietary intake has been linked to dietary restraint (DR) and social desirability (SD), however few investigations have examined the influence of both DR and SD on reporting accuracy and used objective, rather than estimated, measures to determine dietary reporting accuracy. This study investigated accuracy of reporting consumption of a laboratory meal during a 24-hour dietary recall (24HR) in 38 healthy, college-aged, normal-weight women, categorized as high or low in DR and SD. Participants consumed a lunch of four foods (sandwich wrap, chips, fruit, and ice cream) in a laboratory and completed a telephone 24HR the following day. Accuracy of reported energy intake of the meal = ((reported energy intake − measured energy intake) / measured energy intake) × 100 [positive numbers = overreporting]. Overreporting of energy intake occurred in all groups (overall accuracy rate = 43.1 ± 49.9%). SD-high as compared to SD-low more accurately reported energy intake of chips (19.8 ± 56.2% vs. 117.1 ± 141.3%, p < 0.05) and ice cream (17.2 ± 78.2% vs. 71.6 ± 82.7%, p < 0.05). SD-high as compared to SD-low more accurately reported overall energy intake (29.8 ± 48.2% vs. 58.0 ± 48.8%, p < 0.05). To improve accuracy of dietary assessment, future research should investigate factors contributing to inaccuracies in dietary reporting and the best methodology to use to determine dietary reporting accuracy.
Most methods of dietary assessment rely on self-reported information, which is subject to potential inaccuracies and biases (Hill and Davies, 2001, Kretsch et al., 1999, Livingstone and Black, 2003 and Tran et al., 2000). Many factors, such as dietary restraint (DR) and social desirability (SD), have been hypothesized to affect accuracy of self-reported dietary intake, with higher levels of both of these factors associated with underreporting (Asbeck et al., 2002, de Castro, 2006, Horner et al., 2002, Jansen, 1996, Lafay et al., 1997, Novotny et al., 2003, Rennie et al., 2006, Scagliusi et al., 2003, Taren et al., 1999 and Tooze et al., 2004). To identify underreporting, the majority of these studies compared reported dietary intake to estimated energy expenditure (Asbeck et al., 2002, de Castro, 2006, Horner et al., 2002, Lafay et al., 1997, Novotny et al., 2003, Rennie et al., 2006, Scagliusi et al., 2003, Taren et al., 1999 and Tooze et al., 2004).
Only one study has examined the influence of the interaction of DR and SD on accuracy of reported intake. In this study men high in SD were more likely to underreport dietary intake when DR was low, with no outcomes found with women (Tooze et al., 2004). Accuracy of reported energy intake was evaluated by comparing reported energy intake from 24-hour dietary recall (24HR) to energy expenditure estimated using doubly-labeled water (DLW).
Taken together, these studies show inaccurate reporting of dietary intake in individuals high in DR and SD when estimated measures are used to determine accuracy of reported energy intake. Thus, the purpose of the present study was to evaluate how DR and SD interact to influence the accuracy of reporting consumption of a laboratory meal during a 24HR in normal-weight, college-aged women using an objective measure of food intake. It was hypothesized that females high in both DR and SD would be the least accurate in reporting dietary intake.
