Air pollution and the risk of diabetes
The world is facing a very rapid rise in diabetes prevalence. Low- and middle-income countries are the worst sufferers. Among several other established risk factors for diabetes, environmental pollution, in particular air pollution, has been recognised as one important and preventable risk factor. Bangladesh is the top-ranked air pollutant country.
Air pollution has been linked to a variety of health issues, including cardiovascular diseases, respiratory diseases, and even diabetes. While the direct causal relationship between air pollution and diabetes is still being studied, there is growing evidence suggesting that exposure to certain pollutants may increase the risk of developing diabetes.
Particulate matter (PM), nitrogen dioxide (NO2), sulphur dioxide (SO2), and ozone (O3) are some of the key air pollutants associated with diabetes risk. These pollutants are often emitted from vehicle exhaust, industrial processes, and other sources.
Several mechanisms have been proposed to explain how air pollution may contribute to diabetes:
1. Inflammation: Exposure to air pollutants can trigger inflammation, which may impair insulin sensitivity and lead to insulin resistance, a precursor to type 2 diabetes. It is associated with obesity and several other chronic complications of diabetes as well.
2. Oxidative stress: Air pollutants can generate reactive oxygen species in the body, leading to oxidative stress. Oxidative stress can damage pancreatic beta cells along with many other cells, which can contribute to insulin secretory defects.
3. Alternation of adaptive levels: Adipokines are hormones secreted by adipose tissue (fat cells) that play a role in regulating metabolism. Air pollution has been shown to alter adipokine levels, potentially contributing to metabolic dysfunction and insulin resistance.
4. Endocrine disruption: Some air pollutants disrupt hormone regulation in the body, including hormones involved in glucose metabolism.
Several epidemiological studies have found associations between air pollution exposure and an increased risk of diabetes or impaired glucose metabolism. For example, a study published in The Lancet Planetary Health in 2018 found that higher outdoor concentrations of fine particulate matter (PM2.5) and nitrogen dioxide (NO2) were associated with an increased risk of diabetes worldwide.
Overall, while more research is needed to fully understand the relationship between air pollution and diabetes, the existing evidence suggests that reducing air pollution levels could potentially help prevent diabetes and improve public health. This underscores the importance of environmental policies aimed at reducing air pollution and promoting clean energy sources.
The writer is an Associate Professor at the Department of Endocrinology & Metabolism of Bangabandhu Sheikh Mujib Medical University (BSMMU).
Email: selimshahjada@gmail.com