A research model of dietary intake in 184 countries, developed by researchers at the Friedman School of Nutrition Science and Policy at Tufts University, estimates that poor diet contributed to over 14.1 million cases of type 2 diabetes in 2018, representing over 70% of new diagnoses globally. The analysis, which looked at data from 1990 and 2018, provides valuable insight into which dietary factors are driving type 2 diabetes burden by world region. The study was published April 17 in the journal Nature Medicine.
Of the 11 dietary factors considered, three had an outsized contribution to the rising global incidence of type 2 diabetes: Insufficient intake of whole grains, excesses of refined rice and wheat, and the overconsumption of processed meat. Factors such as drinking too much fruit juice and not eating enough non-starchy vegetables, nuts, or seeds, had less of an impact on new cases of the disease.
“Our study suggests poor carbohydrate quality is a leading driver of diet-attributable type 2 diabetes globally, and with important variation by nation and over time,” says senior author Dariush Mozaffarian, Jean Mayer Professor of Nutrition and dean for policy at the Friedman School. “These new findings reveal critical areas for national and global focus to improve nutrition and reduce devastating burdens of diabetes.”
Type 2 diabetes is characterized by the resistance of the body’s cells to insulin. Of the 184 countries included in the Nature Medicine study, all saw an increase in type 2 diabetes cases between 1990 and 2018, representing a growing burden on individuals, families, and healthcare systems.
The research team based their model on information from the Global Dietary Database, along with population demographics from multiple sources, global type 2 diabetes incidence estimates, and data on how food choices impact people living with obesity and type 2 diabetes from multiple published papers.
The analysis revealed that poor diet is causing a larger proportion of total type 2 diabetes incidence in men versus women, in younger versus older adults, and in urban versus rural residents at the global level.
Regions where diet had less of an impact on type 2 diabetes cases included South Asia and Sub-Saharan Africa —though the largest increases in type 2 diabetes due to poor diet between 1990 and 2018 were observed in Sub-Saharan Africa. Of the 30 most populated countries studied, India, Nigeria, and Ethiopia had the fewest case of type 2 diabetes related to unhealthy eating.
