A new study from the University of Michigan suggests that apart from eating unhealthy diets and failing to exercise regularly, there is another factor that tips the scale in women’s weight, body mass index (BMI), waist circumference and body fat – air pollution.
Women in their late 40s and early 50s exposed long-term to air pollution, specifically, higher levels of fine particles, nitrogen dioxide and ozone, saw increases in their body size and composition measures, said Mr. Xin Wang, epidemiology research investigator at the U-M School of Public Health and the study’s first author.
Data came from 1,654 white, Black, Chinese, and Japanese women from the Study of Women’s Health Across the Nation. These women, whose baseline median age was nearly 50 years, were tracked from 2000 to 2008.
Annual air pollution exposures were assigned by linking residential addresses with hybrid estimates of air pollutant concentrations. The researchers examined the associations between pollution and the participants’ body size and composition measures. One question they sought to answer was whether these associations differed by physical activity.
Exposure to air pollution was linked with higher body fat, higher proportion fat and lower lean mass among midlife women. For instance, body fat increased by 4.5 percent, or about 2.6 pounds.
Researchers found out that High levels of physical activity, which had been based on the frequency, duration and perceived physical exertion of more than 60 exercises, was an effective way to mitigate and offset exposure to air pollution.