Authors of a recent study finding that underreporting of calorie intake by participants in observational studies based on surveillance data focusing on nutrition and obesity may present a problem to governments and scientists who use such flawed data to set health policy or to test hypotheses. But others disagree.
At issue are the caloric intake data collected through the National Health and Nutrition Examination Survey (NHANES), an ongoing group of studies designed to assess the health and nutritional status of adults and children in the United States. Critics argue the data are flawed because they are based on 24-hour dietary recall, and people surveyed have a tendency to underreport their caloric intake or overstate the amount of the “good” foods (notably vegetables) or water they consume and to understate the amount of “bad” foods (pizza or sugared soda) they ingest. In responding, NHANES proponents acknowledge these biases and say that those conducting the survey use statistical methods to weigh responses that take into account participants’ biases in dietary recall.
Mitka M. Do Flawed Data on Caloric Intake From NHANES Present Problems for Researchers and Policy Makers?. JAMA. 2013;310(20):2137-2138. doi:10.1001/jama.2013.281865