Are immigrants healthier than native-born Canadians? A systematic review of the healthy immigrant effect in Canada.

OBJECTIVES: Immigrants are typically healthier than the native-born population in the receiving country and also tend to be healthier than non-migrants in the countries of origin. This foreign-born health advantage has been referred to as the healthy immigrant effect (HIE). We examined evidence for the HIE in Canada.
DESIGN: We employed a systematic search of the literature on immigration and health and identified 78 eligible studies. We used a narrative method to synthesize the HIE across different stages of the life-course and different health outcomes within each stage. We also examined the empirical evidence for positive selection and duration effects - two common explanations of migrants' health advantage and deterioration, respectively.
RESULTS: We find that the HIE appears to be strongest during adulthood but less so during childhood/adolescence and late life. A foreign-born health advantage is also more robust for mortality but less so for morbidity. The HIE is also stronger for more recent immigrants but further research is needed to determine the critical threshold for when migrants' advantage disappears. Positive selection as an explanation for the HIE remains underdeveloped.
CONCLUSIONS: There is an absence of a uniform foreign-born health advantage across different life-course stages and health outcomes in Canada. Nonetheless, it remains the case that the HIE characterizes the majority of contemporary migrants since Canada's foreign-born population consists mostly of core working age adults.