The Nutrition Transition from 2013-2022 and its Association with Body Mass Index among Participants of the Dhulikhel Heart Study, Nepal

Abstract

Almost every country in the world has experienced dramatic shifts in diet quality marked by increased consumption of ultra-processed foods during a period of three to four decades. A nutrition transition is a change in population-level diet due to shifts in food availability, as well as other economic, social, demographic, and health factors. A study has reported that the average proportion of energy derived from total fat has grown considerably from 13% in 1970 to 17% in 2010 in Nepal. Obesity has also increased from 21% of women to 27% in the urban population. This study aims to measure the nutrition transition in terms of changes in dietary intake from 2013 to 2022 and to assess the associations between 9-year dietary change and body mass index (BMI) among the participants of the Dhulikhel Heart Study (DHS). In this analysis, we utilized data from 307 participants of the DHS, a longitudinal observational cohort study (2013-2022) investigating heart health in Dhulikhel, Nepal. The study was comprised of two exams: wave 1 in 2013 and wave 2 in 2022. This retrospective study used the data from the specific sections “Food and Nutrition” and “Anthropometric Assessment” collected at each exam. DHS used a semiquantitative validated Food Frequency Questionnaire (FFQ) to assess participants’ usual dietary intake. BMI was assessed using weight and height data collected at each home visit. Multivariate regression was used to evaluate the relationship between the nutrition transition score and BMI. The mean age of the participants at wave 1 was 42.8 (±15.1) years and at wave 2 it was 50 (±15.1) years. We found that 19% and 30% of the participants were hypertensive in DHS waves 1 and 2, respectively. We observed changes in both healthy and unhealthy GDQS food group during the 9-year follow-up. The mean GDQS score was 28.6 for the DHS participants at wave 1 and 24.9 at wave 2, indicating poorer diet quality at the second wave. After adjusting for age, education, sex, ethnicity, and total caloric intake, BMI and GDQS score of DHS wave 1 participants were not significantly associated (Coefficient: -0.04, SE: 0.07, p= 0.51), whereas in wave 2, BMI and GDQS score were associated (Coefficient: 0.20, SE: 0.07, p= 0.005). In the model evaluating BMI at wave 2 and the nutritional transition score. for every one unit increase in diet quality, BMI was 0.009 kg/m2 higher (Coefficient: 0.09, SE: 0.05, p=0.06). This study suggests that diet quality has declined, and obesity has increased during a 9-year follow-up in the DHS. However, associations between the nutritional transition score and BMI were not found. Results may have been affected by small sample size, variables not included in the models, and residual confounding.