The Top 15 Most Stressful Cities

Four out of America's 15 most stressful cities are in California alone. Los Angeles steals the gold at number with cities including New York, Chicago, Washington D.C., and San Diego trailing behind.

There were other factors that were used to create this list. Greenfield mentions that "because air quality plays a role in mental well being, we looked at the number of days per year with dangerous ozone levels, using the American Lung Association's State of the Air 2011 report, which is based in part on data supplied by the Environmental Protection Agency.

Other important factors that were looked at were finances because even if you're employed, you're working tremendously long hours causing stress along with traffic congestion. Kathleen Hall, founder and CEO of the Stress Institute, based in Atlanta. Traffic congestion and long commutes are also serious anxiety producers she says, adding, "Commuters can experience greater stress than fighter pilots in battle."