Diabetes type 2 is a chronic disease that affects how the body metabolizes sugar, resulting in high blood sugar levels. It is a serious health issue that can result in complications like heart disease, stroke, and kidney failure. According to the study, people who eat a diet high in sugar, processed foods, and red meat and low in fruits, vegetables, and whole grains are more likely to develop type 2 diabetes. This diet has also been linked to obesity, which is a major risk factor for type 2 diabetes.
A research model of dietary intake in 184 countries developed by researchers at Tufts University’s Friedman School of Nutrition Science and Policy estimates that poor diet contributed to over 14.1 million cases of type 2 diabetes in 2018, accounting for more than 70% of new diagnoses worldwide. The study, which looked at data from 1990 to 2018, provides valuable insight into which dietary factors contribute to the global burden of type 2 diabetes. The findings were published in the journal Nature Medicine.
Three of the 11 dietary factors studied contributed significantly to the rising global incidence of type 2 diabetes: insufficient intake of whole grains, excesses of refined rice and wheat, and excessive consumption of processed meat.
“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.”
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. These new findings reveal critical areas for national and global focus to improve nutrition and reduce the devastating burdens of diabetes.
Dariush Mozaffarian
Type 2 diabetes is distinguished by the body’s cells’ resistance to insulin. Between 1990 and 2018, all 184 countries included in the Nature Medicine study saw an increase in type 2 diabetes cases, representing a growing burden on individuals, families, and healthcare systems.
The research team based their model on data from the Global Dietary Database, population demographics from multiple sources, global type-2 diabetes incidence estimates, and data from multiple published papers on how food choices affect people living with obesity and type-2 diabetes.
At the global level, the study found that poor diet causes a greater proportion of total type 2 diabetes incidence in men versus women, younger versus older adults, and urban versus rural residents.
Regionally, Central and Eastern Europe and Central Asia had the highest number of type 2 diabetes cases linked to diet, particularly in Poland and Russia, where diets are high in red meat, processed meat, and potatoes. In Latin America and the Caribbean, especially in Colombia and Mexico, the incidence was also high, which was attributed to the high consumption of sugary drinks, processed meat, and a low intake of whole grains.
South Asia and Sub-Saharan Africa had less of an impact on type 2 diabetes cases, though Sub-Saharan Africa saw the greatest increase in type 2 diabetes due to poor diet between 1990 and 2018. Of the 30 most populated countries studied, India, Nigeria, and Ethiopia had the fewest case of type 2 diabetes related to unhealthy eating.
“Left unchecked and with incidence only projected to rise, type 2 diabetes will continue to impact population health, economic productivity, health care system capacity, and drive health inequities worldwide,” says first author Meghan O’Hearn. She conducted this research while a Ph.D. candidate at the Friedman School and currently works as Impact Director for Food Systems for the Future, a non-profit institute and for-profit fund that enables innovative food and agriculture enterprises to measurably improve nutrition outcomes for underserved and low-income communities. “These findings can help inform nutritional priorities for clinicians, policymakers, and private sector actors as they encourage healthier dietary choices that address this global epidemic.”
Other recent studies have estimated that suboptimal diet is responsible for 40% of type 2 diabetes cases worldwide, which is lower than the 70% reported in the Nature Medicine paper. The researchers attribute this to new information in their analysis, such as the first-ever inclusion of refined grains, which was one of the leading contributors to diabetes burdens, and updated data on dietary habits based on national individual-level dietary surveys rather than agricultural estimates. The researchers also mention that they presented the uncertainty of these new estimates, which can be refined as new data becomes available.
