A new study from the United States has linked the rising incidence of diabetes globally to air pollution.

Conducted by the Washington University School of Medicine in St. Louis and the Veterans Affairs (VA) St. Louis Health Care System, the research reveals that outdoor air pollution also contributes to the problem along with other drivers such as an unhealthy diet, sedentary lifestyles and obesity.

Diabetes affects more than 420 million people worldwide.

According to the study’s senior author and assistant professor of medicine at Washington University, Ziyad Al-Aly, MD, there is increased risk of diabetes even at low levels of air pollution currently considered safe by the U.S. Environmental Protection Agency (EPA) and the World Health Organization (WHO).

Particulate matter such as airborne dust, dirt, smoke, soot and liquid droplets can enter the lungs and the bloodstream, leading to heart disease, stroke, cancer and kidney disease.

These pollutants can also affect insulin production, preventing the conversion of blood glucose into energy, and ultimately leading to diabetes. Air pollution is believed to have contributed to 3.2 million new diabetes cases globally in 2016, representing about 14 percent of all new diabetes cases.

Pollution-linked diabetes is estimated to have destroyed 8.2 million years of healthy life in 2016.

For the study, researchers from the Washington University School of Medicine worked with scientists at the Veterans Affairs' Clinical Epidemiology Center to analyse data from 1.7 million U.S. veterans who were followed for an average of 8.5 years. None of the veterans had a history of diabetes.

Findings from the study published recently in The Lancet Planetary Health also reveal that low-income economies such as India, Afghanistan, Papua New Guinea and Guyana face a higher risk from pollution-linked diabetes than richer countries such as France, Finland and Iceland.