Etiology of Obesity Over the Life Span: Ecologic and Genetic Highlights from New Zealand Cohorts

The origins of the New Zealand population are highly diverse. New Zealand Māori are the indigenous peoples with a population of approximately half a million (~12 %), with the remainder comprising predominantly European/Caucasian (~50 %), Pacific Island Polynesian (~28 %) and Asian (~10 %) peoples. With a prevalence of overweight and obesity of 65 % for adults >15 years of age, of which 28 % have a BMI > 30 kg/m2, New Zealand has been ranked third highest in a global OECD obesity review, behind only the US and Mexico. Levels of childhood obesity are also significant, with 31 % of New Zealand’s children either overweight or obese. Few gender differences exist, but there are significant differences between ethnicities (Asian > European Caucasian > Māori > Pacific) with disproportionate representation by those poorer and with less formal education. A high 62 % of Pacifika are obese and virtually the entire adult population has a BMI >25 kg/m2. Public health measures to limit progressive increases in weight are unsuccessful, and clearly should be priority for government focused on disease prevention.