Food consumption and dietary factors involved in health and disease in Nikkeis: systematic review

OBJECTIVE: To analyze food consumption and dietary factors involved in the Nikkei population's health and disease processesMETHODS: A systematic review of observational studies that described Nikkeis' food intake was carried out in electronic databases Lilacs, SciELO and PubMed/Medline databases, from 1997 to 2012. Initially, 137 titles and abstracts were analyzed, excluding intervention studies, those which only presented metabolite and vitamin plasma levels and those which did not meet the objective of this study. Of these, 38 studies were selected and evaluated using a method based on Downs & Black (1998), adapted for observational studies, leaving 33 studies to be analyzed.RESULTS: Few studies about Nikkei food intake were found outside of Hawaii, in the United States, and Sao Paulo (mainly in the city of Bauru) in Brazil. The total energy intake of Japanese-Brazilians had an elevated fat contribution, decreasing carbohydrate and protein intake. In the United States, the prevalence of Japanese-Americans who consumed high density energy food was elevated. The Niseis (children of immigrants) presented, on average, higher intake of Japanese food products, while the Sanseis (grandchildren of immigrants) showed more Westernized dietary habits.CONCLUSIONS: Although some Japanese food habits have been maintained, the Nikkeis' dietary intake reveals a high prevalence of typical Westernized food intake (high in processed food, fat and sodium, and poor in fiber), that may be contributing to the increasing development of chronic disease in this population.