The study, jointly conducted by Universiti Kebangsaan Malaysia, the University of Auckland and the University of Otago, suggested that the HDHI offers a practical method of determining the diet quality of subgroups in New Zealand’s population.
A total of 3,993 participants aged 19 to 98 were surveyed, with factors such as cooking methods, ethnic group, socioeconomic status, type and amount of food and beverage consumed, alcohol consumption, tobacco use, and height and weight all taken into account.
Subsequently, it found that ethnicity and socioeconomic status played significant role in the dietary quality of adults in New Zealand. The study stated: “The mean HDHI scores were highest among women, older age groups, non-Māori or pacific ethnic groups, and less socioeconomically deprived groups”, adding that “diet quality was found to follow a socioeconomic gradient”.
Indeed, the mean HDHI scores of Māori and Pacific ethnic groups were approximately 15% lower than that of their African, Asian, European, Latin American and Middle Eastern counterparts, with 72% of Māori and 81% reportedly living in New Zealand’s “two most deprived areas”.
When it came to alcohol consumption, the HDHI scores of light to moderate drinkers were comparable to former and non-drinkers, “which supports the notion that moderate alcohol consumption (up to four drinks a day for men and two drinks a day for women) can be part of a healthy diet”.
This study also found that higher HDHI scores were associated with better nutritional biomarker levels.
"Consistent with findings from dietary recall data, lower levels of urinary sodium, and higher levels of whole blood folate, serum folate and red blood cell folates, and plasma selenium were found to be associated with increasing HDHI scores," it noted.
Ultimately, the study’s main strength was identified as “the simplicity of the HDHI, which is easy to administer” and “examines various aspects of dietary habits that are important indicators of diet quality”.
However, it did not assess information on physical activity, and concluded that “further research is recommended to validate the HDHI in a longitudinal study of nutrition and health outcomes”.
“Development of a Healthy Dietary Habits Index for New Zealand Adults”
Authors: Jyh Eiin Wong, Jillian J. Haszard, Anna S. Howe, Winsome R. Parnell, Paula M.L. Skidmore