(NaturalNews) Oxygen is the single most important nutrient for our survival and wellbeing. While a healthy human being can go for weeks or even months without food, or last several days without water, cut off his or her air supply, and the person is unlikely to make it past a few minutes, if not seconds. It is then sometimes a wonder why more attention is not given to clean air as an important element for optimal health. Clean air indeed plays a great part in promoting good health and longevity, as revealed by a recent study conducted at Brigham Young University and Harvard School of Public Health. It had found that the lower the levels of particulate air pollution, the better life expectancy becomes.
Details of Study
The study, published in the New England Journal of Medicine, had looked at changes in air pollution from about 1980 to about 2000 as well as the life expectancies of residents in 51 United States cities during that period. Other influencing factors, such as income changes, education levels, migration, smoking trends and population demographics were accounted for using advanced statistical models.
"Life expectancy is the single most comprehensive summary of how people's longevity is affected by factors like air pollution that cause early death. We were able to use routine mortality statistics to track longevity in all cities over a long period of time and analyze how it has been influenced by changes in air pollution," said Majid Ezzati, an associate professor of international health at Harvard School of Public Health, who was a member of the study team.
Findings of Study
According to environmental epidemiologist Joel Schwartz from the Harvard School of Public Health, who was not part of the study team, it is a well-known fact that particulate air pollution has an adverse impact on life expectancy. But he said that decision makers in the government would really want to know "[i]f I spend the money to reduce pollution, what really happens?"
That is where this study helps a great deal. It not only showed a positive correlation between clean air and longer life, it managed to provide a quantifiable estimation of the association, too. Its findings revealed that the average life expectancy across the 51 cities rose by 2.72 years over the two-decade period of the study, and about 5 months of this increase, or about 15%, can be attributed to decreased air pollution.
Further, in cities which had started out being the most polluted, for example Buffalo and Pittsburgh, the average improvement to life expectancy stretched up to about 10 months. But there was good news for the "cleaner" cities too - even these cities experienced life expectancy gains with further reduction in air pollution.
Delving deeper into more technical details, the study's findings had revealed that every reduction of 10 micrograms per cubic meter of particulate pollution affected a resultant average increase in life expectancy of over 7 months. This is roughly consistent with what previous smaller studies had found.
The particulates mentioned here are called fine particulates, as their diameter is less than 2.5 microns. Their minute size allows them to get into the small air passages of the lungs, and these tiny particles have been shown many times to negatively affect cardiovascular and pulmonary health. For example, a very recently published German study had found that people who lived near traffic had an elevated risk of developing atherosclerosis (hardening of the arteries), which in turn increases the risk of heart disease (read more about that study at http://www.naturalnews.com/025533.html).
These small particulates are typically produced by cigarettes, engines, coal power plants, as well as other urban activities. Bigger particulates have a more significant impact on visibility, but cause less health problems because the body is able to filter them out.
"Such a significant increase in life expectancy attributable to reducing air pollution is remarkable. We find that we're getting a substantial return on our investments in improving our air quality. Not only are we getting cleaner air that improves our environment, but it is improving our public health," said C Arden Pope III, an epidemiologist at Brigham Young University and the leader of the study.
"There is an important positive message here that the efforts to reduce particulate air pollution concentrations in the United States over the past 20 years have led to substantial and measurable improvements in life expectancy," said Douglas Dockery, chair of the Department of Environmental Health at Harvard School of Public Health, a member of the research team.
It is good news that efforts to improve air quality have paid tangible dividends. But, at the same time, Pope feels that more can be done. In the early 80s, the average concentration of fine particulates in the air was about 21 micrograms per cubic meter. This went down by a third, to about 14 micrograms per cubic meter, by 2000. "It's reasonable to expect that we could reduce it by that much again, but then we reach a point of substantially diminishing marginal returns," he added.
Let us hope for even fresher air in the days ahead.