Health Expectancies (HEs) for New Zealand show significant differentials between Maori and non-Maori, but also by gender and period. These differentials correlate with findings from both generation and synthetic life-tables relating to New Zealand’s epidemiologic transition. At the beginning of that transition quartile 1 (Q(1)), and Median (Med) d(x) values were close and centred at young ages; during the transition the gap became very wide; at the transition’s end the gap again narrowed. Cohort and synthetic trends in d(x), l(x), M, Qs and Meds are reviewed and linked to recent HEs. Data point to epidemic polarisation. Cohort analysis allows the evaluation of the role of past experiences on the recent HEs, and thus point to possible strategies for reducing gaps in both d(x), and HEs.