The Food Similarity Index: A New Measure of Dietary Acculturation Based on Dietary Recall Data

This study introduces a flexible indicator of dietary acculturation that measures immigrants’ eating behavior relative to U.S.-born persons. Using 24-hour dietary recall data from the continuous National Health and Nutrition Examination Survey pooled across multiple years from 1999/00 through 2009/10, we developed and tested the validity of the “Food Similarity Index” (FSI), which indicates the similarity of the foods consumed by individuals to the foods most commonly consumed by same-aged U.S-born persons of all racial/ethnic groups. We demonstrate its utility here for children and adults of four racial-ethnic groups. FSI was positively associated with the consumption of common American foods and negatively associated with eating Hispanic and Asian foods. In addition, FSI was associated with generational status among all racial/ethnic groups and duration of U.S. residence among Hispanics. FSI was also negatively associated with the Healthy Eating Index 2010. The FSI enables researchers to compare immigrants’ dietary patterns over generations and across groups. It can be used to study how dietary acculturation shapes health risk factors and diseases.