Health

Obesity

Obesity is an excessively high amount of body fat in relation to lean body mass, defined as having a Body Mass Index (BMI, calculated as kg/m²) of 30+, or equivalent for those aged under 18 years [22]. Obesity is associated with an increased risk of a number of health conditions, including type 2 diabetes, ischaemic heart disease, high blood pressure, some cancers, some forms of arthritis, and stroke [23]. Rates of obesity have increased in almost all countries in the past three to four decades and New Zealand now has one of the highest rates of obesity in the world [24,25]. Most of this increase has been attributed to increased access to foods that are more processed, affordable, and effectively marketed [26]. Energy-dense and nutrient-poor foods have become the most affordable way to meet daily calorie needs compared to nutrient-rich and high-quality foods, resulting in low income groups generally having a poorer diet than high income groups [27]. Policies and programmes that make it easier to eat healthily and exercise regularly are required to reduce obesity at the population level.

This indicator presents the proportion of those 15 years and over who are obese (Body Mass Index, calculated as kg/m², of 30+, or equivalent for those aged <18 years), using New Zealand Health Survey data.

The figure shows that approximately three-in-ten adult respondents (29.4%) were obese across the Canterbury DHB region, in 2016/17 (slightly lower than New Zealand overall, 31.2%, difference not statistically significant). The proportion of respondents aged 15 years and over who are obese in New Zealand has increased statistically significantly between 2011/12 and 2016/17 (27.9% increasing to 31.2%). The proportion of Canterbury respondents aged 15 years and over who are obese has also increased between the 2011/12 and 2016/17 time-points (23.4% increasing to 29.4%) however, the differences are not statistically significant.

The figure shows that the proportion of Canterbury DHB region respondents, aged 15 years and over, who were obese was highest for Pacific people during the 2011–14 and 2014–2017 time periods, compared with Māori and Asian respondents (in 2014–2017, Pacific, 63.4%; Māori, 45.6%; Asian, 11.2%; compared with 26.6% for the total population). The proportion of adult Māori and Asian respondents who are obese has remained unchanged over the time period shown (45.9% and 10.6%, 2011–14 compared with 45.6% and 11.2%, 2014–17). Pacific and Māori respondents were statistically significantly more likely to be obese compared with Asian respondents, and the total population, in the Canterbury DHB region, in both time periods.

The figure shows that the proportion of respondents aged 15 years and over who are obese in the Canterbury DHB region is higher for the older age groups, in particular for those aged 45 to 64 years (33.8%) and those aged 65+ years (33.7%) (i.e., a statistically significantly higher proportion for both age groups than for those aged 15–24 years, in both time periods).

The figure shows that statistically similar proportions of female and male respondents, aged 15 years and over, are obese in the Canterbury DHB region (28.8% and 24.9% respectively, for 2014–17).

The figure indicates that adult obesity in the Canterbury DHB region is associated with socioeconomic deprivation. The differences indicate that respondents (aged 15 years and over) who live in neighbourhoods that have the least deprived NZDep13 scores are less likely to be obese compared with respondents who live in neighbourhoods with the most deprived NZDep13 scores (for 2014–17, Quintile 1, 25.2%; Quintile 2, 24.2%; Quintile 3, 27.1%; Quintile 4, 30.1%; and Quintile 5; 33.9%). However, the differences are not statistically significant.

Data Sources

Source: Ministry of Health.
Survey/data set: New Zealand Health Survey to 2017. Access publicly available data from the Ministry of Health website www.health.govt.nz/publication/regional-results-2014-2017-new-zealand-health-survey
Source data frequency:  Survey conducted continuously with data reported annually. Regional results (pooled data) released every 3 years.

View technical notes and data tables for this indicator.

Updated: 21/11/2018