Exposure to highly polluted air has been linked with weight gain, and cardio-respiratory and metabolic anomalies in a new study published in the journal of the Federation of American Societies for Experimental Biology (FASEB).
The researchers of the study conducted their experiments on pregnant rats and their offspring. The rats were divided into two groups: one was placed in a chamber filled with outdoor Beijing air and the other in a chamber equipped with an air filter to keep most of the pollutants out. The pregnant rats in both groups had the same diet.
According to the observations made by the scientists, the pregnant rats’ lungs and livers were heavier and marked with increased tissue inflammation after only 19 days in the chamber.
When compared with the rats from the filtered chamber, this group of rats had:
- 97% higher total cholesterol
- 50% higher LDL cholesterol
- 46% higher levels of triglycerides
- greater insulin resistance level
The offspring of the rats that were in the first group showed similar changes.
Also, adverse effects were more pronounced after eight weeks in the chamber than after only 3 weeks; the rats having gained weight were 18% weightier at 8 weeks while they were only 10% heavier at 3 weeks.
From the results, the authors conclude that air pollution might cause metabolic dysfunction which is a precursor to obesity. Furthermore, they say that the negative consequences entailing continuous inflammation and metabolism disorders only happen with long-term exposure to the pollutants.
The study supports previous findings that showed how air pollution was associated with organ and circulatory system inflammation, greater insulin resistance, and modified fat tissue.
Senior author Junfeng “Jim” Zhang from Duke University explains that chronic inflammation is linked with obesity which is, in turn, related with diabetes, and that chronic exposure to air pollution entails a greater risk of developing obesity. He also holds the opinion that the findings, if verified in humans, will support the “need to reduce air pollution, given the growing burden of obesity in today’s highly polluted world“.