Abstract / Summary
A vital aspect of health affected by immigration is diet quality. Previous investigations on this topic have yielded inconsistent results. This systematic review aims to summarize and organize research findings about diet quality among adult immigrants compared with non-migrants. A comprehensive search was done on electronic databases of PubMed, Scopus and Web of Science to find relevant articles published from 2000 to November 2024. Inclusion criteria included quantitative studies of diet quality among population of adult immigrants compared with native-born population of either the origin or the destination country, or compared with before immigration. Nineteen studies met the inclusion criteria and were included in this systematic review. Fifteen studies compared immigrants with the native-born population of the destination country; of these, seven reported higher diet quality among immigrants, while two reported lower diet quality. The remaining six studies in this category reported mixed results for different immigrant groups or different diet quality indices. Additionally, five studies compared immigrants with the native-born population of their original countries. Among these, three studies reported higher diet quality, one reported lower diet quality, and the remaining study found no significant difference. Finally, one study compared diets pre- and post-immigration and observed a decline in diet quality. Most immigrant groups had higher diet quality compared with non-migrants. In contrast, certain immigrant groups, particularly some socioeconomically underprivileged groups, exhibited poorer diet quality. The specific method of diet quality assessment and factors related to the nature of immigration, such as length of residence in destination, educational, financial and occupational status, and food culture could contribute to the observed heterogeneity. In conclusion, diet quality of immigrants is a function of multiple social, cultural, and economic factors, especially the immigrants’ socio-economic status.