Experts at Washington University School of Medicine are reporting that outdoor air pollution is directly related to an increased risk of diabetes. This correlation was found to be strong even in regions where pollution levels are considered to be safe.
Diabetes affects more than 420 million people worldwide including 30 million Americans, and is growing at one of the fastest rates of any disease. An unhealthy diet, obesity, and a sedentary lifestyle are all major diabetes risks. The new study identifies outdoor air pollution as yet another factor contributing to the onset of diabetes.
Pollution is believed to reduce insulin production and trigger inflammation. This prevents the body from converting blood glucose into energy that the body needs.
“Our research shows a significant link between air pollution and diabetes globally,” said senior author Dr. Ziyad Al-Aly. “We found an increased risk, even at low levels of air pollution currently considered safe by the U.S. Environmental Protection Agency (EPA) and the World Health Organization (WHO). This is important because many industry lobbying groups argue that current levels are too stringent and should be relaxed. Evidence shows that current levels are still not sufficiently safe and need to be tightened.”
This study is the first to attempt to quantify the connection between air pollution and diabetes.
“Over the past two decades, there have been bits of research about diabetes and pollution,” said Dr. Al-Aly. “We wanted to thread together the pieces for a broader, more solid understanding.”
The team collaborated with scientists at the Veterans Affairs’ Clinical Epidemiology Center to analyze the connection between particulate matter and the risk of diabetes. They examined data from 1.7 million U.S. veterans who did not have any history of diabetes and tracked them for an average of 8.5 years.
The researchers compared medical information on the patients to data from the EPA’s land-based air monitoring systems as well as satellite data from NASA.
The experts also reviewed all studies linking diabetes and outdoor air pollution, and developed a model that can be used to measure diabetes risks across various pollution levels.
Furthermore, by analyzing data from the Global Burden of Disease study, the researchers were able to estimate annual cases of diabetes and healthy years of life lost due to pollution.
According to the analysis, pollution contributed to 3.2 million new diabetes cases in 2016, which is around 14 percent of all new diabetes cases documented worldwide. That year, a total of 8.2 million years of healthy life were lost due to pollution-linked diabetes.
In the United States, 150,000 new cases of diabetes were attributed to air pollution annually, and 350,000 years of healthy life were found to be lost per year.
The findings of the study indicate that lower levels of pollution can lead to a significant drop in the number of diabetes cases around the world, including countries with the highest levels of pollution such as India and those with less pollution such as the United States.
The research is published in the journal Lancet Planetary Health.